[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379600591
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379575397
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
 
 Review comment:
   Added
   - Cannot create aggregates in virtual keyspaces; but may run aggregate 
functions on select


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

-
To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org
For additional commands, e-ma

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379571959
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379571071
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379571223
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379570827
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379570237
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379569957
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379569393
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
 
 Review comment:
   removed


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

--

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379569285
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
 
 Review comment:
   Modified.


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

-
To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org
For additional commands, e-mail: pr-h...@cassandra.apache.org

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379568915
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
 
 Review comment:
   Added.


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

-
To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org
For additional commands, e-mail: pr-h...@cassandra.apache.org

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379568765
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379568536
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379568407
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
 
 Review comment:
   Added 
   - the partitioner sorts in order of partition keys instead of by their hash
   - tables are local only and non distributed


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

-
To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org
For additional commands, e-mail: pr-h...@cassandra.apache.org

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379567768
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
 
 Review comment:
   I have added earlier that some of these are "likely to change". Best to keep 
the detail as currently supported. And when any of these change the page could 
be updated.


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

-
To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org
For additional commands, e-mail: pr-h...@cassandra.apache.org

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379567935
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
+
+::
+
+ cqlsh> DESCRIBE KEYSPACE system_views
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh> DESCRIBE KEYSPACE system_virtual_schema;
+ 'NoneType' object has no attribute 'export_for_schema'
+ cqlsh>
+
+Virtual Table Limitations
+^
+
+Virtual tables and virtual keyspaces have some limitations such as:
+
+- Cannot alter virtual keyspaces
+- Cannot drop virtual keyspaces
+- Cannot alter virtual tables
+- Cannot drop virtual tables
+- Cannot truncate virtual tables
+- Expiring columns are not supported by virtual tables
+- Conditional updates are not supported by virtual tables
+- Cannot create tables in virtual keyspaces
+- Cannot perform any operations against virtual keyspace
+- Secondary indexes are not supported on virtual tables
+- Cannot create functions in virtual keyspaces
+- Cannot create types in virtual keyspaces
+- Materialized views are not supported on virtual tables
+- Virtual tables don't support DELETE statements
+- Cannot CREATE TRIGGER against a virtual table
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot include a virtual table statement in a logged batch
+- Mutations for virtual and regular tables cannot exist in the same batch
+- Conditional BATCH statements cannot include mutations for virtual tables
+- Cannot create aggregates in virtual keyspaces
+
+Listing and Describing Virtual Tables
+^
+
+Virtual tables in a virtual keyspace may however be listed with ``DESC 
TABLES``.  The ``system_views`` virtual keyspace tables include the following:
+
+::
+
+ cqlsh> USE system_views;
+ cqlsh:system_views> DESC TABLES;
+   clientsinternode_inbound
+ disk_usage   sstable_taskscaches   
+ local_writesmax_partition_size  local_reads   
+ coordinator_writes  internode_outbound  thread_pools  
+ local_scans coordinator_reads   settings 
+
+Some of the salient virtual tables in system_views virtual keyspac

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379566143
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
+- Virtual tables are not replicated
+- Virtual tables have no associated SSTables
+- Consistency level of the queries sent virtual tables are ignored
+- Virtual tables are managed by Cassandra and a user cannot run  DDL to create 
new virtual tables or DML to modify existing virtual tables
+- Virtual tables are created in special keyspaces and not just any keyspace
+- All existing virtual tables use LocalPartitioner
+
+Virtual Keyspaces
+^
+
+Apache Cassandra 4.0 has added two new keyspaces for virtual tables: 
``system_virtual_schema`` and ``system_views``. Run the following command to 
list the keyspaces.
+
+::
+
+ cqlsh> DESC KEYSPACES;
+ system_schema  system   system_distributed  system_virtual_schema
+ system_auth  system_traces   system_views
+
+The ``system_virtual_schema keyspace`` contains schema information on virtual 
tables. The ``system_views`` keyspace contains the actual virtual tables. The 
virtual keyspaces metadata is not exposed through ``DESCRIBE`` statement, which 
returns an error message:
 
 Review comment:
   Removed statement about DESCRIBE.


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

-
To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org
For additional commands, e-mail: pr-h...@cassandra.apache.org

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379561875
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
+ 
+How  are Virtual Tables different from regular tables?
+^^
+
+Virtual tables and virtual keyspaces are quite different from regular tables 
and keyspaces respectively such as:
+
+- Virtual tables are read-only 
 
 Review comment:
   Rather than list that is not currently supported, I have added:
   
   - Virtual tables are read-only, but it is likely to change


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

-
To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org
For additional commands, e-mail: pr-h...@cassandra.apache.org

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379561239
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
+- Expose YAML configuration information
+- Expose other MBean data
 
 Review comment:
   Removed mbeans/jmx


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

-
To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org
For additional commands, e-mail: pr-h...@cassandra.apache.org

[GitHub] [cassandra] dvohra commented on a change in pull request #402: New/virtualtables

[GitBox]

dvohra commented on a change in pull request #402: New/virtualtables
URL: https://github.com/apache/cassandra/pull/402#discussion_r379561053
 
 

 ##
 File path: doc/source/new/virtualtables.rst
 ##
 @@ -0,0 +1,586 @@
+.. Licensed to the Apache Software Foundation (ASF) under one
+.. or more contributor license agreements.  See the NOTICE file
+.. distributed with this work for additional information
+.. regarding copyright ownership.  The ASF licenses this file
+.. to you under the Apache License, Version 2.0 (the
+.. "License"); you may not use this file except in compliance
+.. with the License.  You may obtain a copy of the License at
+..
+.. http://www.apache.org/licenses/LICENSE-2.0
+..
+.. Unless required by applicable law or agreed to in writing, software
+.. distributed under the License is distributed on an "AS IS" BASIS,
+.. WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+.. See the License for the specific language governing permissions and
+.. limitations under the License.
+
+Virtual Tables
+--
+
+Apache Cassandra 4.0 implements virtual tables (`CASSANDRA-7622
+`_).
+
+Definition
+^^
+
+A virtual table is a table that is backed by an API instead of data explicitly 
managed and stored as SSTables. Apache Cassandra 4.0 implements a virtual 
keyspace interface for virtual tables. Virtual tables are specific to each 
node. 
+
+Objective
+^
+
+A virtual table could have several uses including:
+
+- Expose JMX data/metrics through CQL
 
 Review comment:
   Removed JMX


This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

-
To unsubscribe, e-mail: pr-unsubscr...@cassandra.apache.org
For additional commands, e-mail: pr-h...@cassandra.apache.org