[
https://issues.apache.org/jira/browse/CASSANDRA-20331?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17928816#comment-17928816
]
Lukasz Antoniak commented on CASSANDRA-20331:
---------------------------------------------
{quote}Do you mean checking pre-existing constraints in the schema table and
potentially rejecting DDL statements prior to sending them to the server?
{quote}
Yes, you understand correctly. I have raised this issue with [~smiklosovic]
mostly to provide this constraint catalog tables for driver's "keyspace
metadata" functionality. Note that Java driver exposes keyspace metadata API
which allows applications to browse schema definition in more typed and parsed
way. This API includes for example functions and we even parse name, parameter
types, etc. Review attached screenshot. I thought that we should implement
something analogical for column constraints. This can be further used by JDBC
drivers implemented on top of CQL drivers.
> Expose constraints in system_schema.column_constraints
> ------------------------------------------------------
>
> Key: CASSANDRA-20331
> URL: https://issues.apache.org/jira/browse/CASSANDRA-20331
> Project: Apache Cassandra
> Issue Type: Task
> Components: Feature/Constraints
> Reporter: Stefan Miklosovic
> Assignee: Bernardo Botella Corbi
> Priority: Normal
> Fix For: 5.x
>
> Time Spent: 20m
> Remaining Estimate: 0h
>
> There is already system_schema.column_masks
> {code}
> CREATE TABLE system_schema.column_masks (
> keyspace_name text,
> table_name text,
> column_name text,
> function_argument_nulls frozen<list<boolean>>,
> function_argument_types frozen<list<text>>,
> function_argument_values frozen<list<text>>,
> function_keyspace text,
> function_name text,
> PRIMARY KEY (keyspace_name, table_name, column_name)
> ) WITH CLUSTERING ORDER BY (table_name ASC, column_name ASC)
> {code}
> We need this table with constraints of each column, similar to masks. Right
> now there is no programmatic way to realize what constraints a column has.
> This will come handy when Java Driver will start to support this. They will
> just scan system_schema.column_constraints and they can e.g. fail the query
> on client side it will never reach the server ...
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
