amogh-jahagirdar commented on code in PR #6723: URL: https://github.com/apache/iceberg/pull/6723#discussion_r1148745510
########## docs/branching-and-tagging.md: ########## @@ -0,0 +1,82 @@ +--- +title: "Branching and Tagging" +url: branching +aliases: + - "tables/branching" +menu: + main: + parent: Tables + weight: 0 +--- + +<!-- + - 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. + --> + +# Branching and Tagging + +## Overview + +Iceberg table metadata maintains a log of snapshots which represent the changes applied to a table. +Snapshots are fundamental in Iceberg as they are the basis for reader isolation and time travel queries. +For controlling metadata size and storage costs, Iceberg provides snapshot lifecycle management procedures such as [`expire_snapshots`](../../spark/spark-procedures/#expire-snapshots) for removing unused snapshots and no longer neccessary data files based on table snapshot retention properties. + +**For more sophisticated snapshot lifecycle management, Iceberg also supports branches and tags which are named references to snapshots.** Branches are independent lineages of snapshots and point to the head of the lineage. +Branches and tags have independent lifecycles with regards to snapshot retention during `expireSnapshots`. + +Branching and tagging can be used for handling GDPR requirements and retaining important historical snapshots for auditing. +Branches can also be used as part of data engineering workflows, for enabling experimental branches for testing and validating new jobs. +See below for some examples of how branching and tagging can facilitate these use cases. + + + +The above diagram shows an example of using tag to retain historical snapshots. +In this case a end of year tag is created for the final snapshot in the year, and the tagged snapshot has a retention of 5 years for compliance reasons. Review Comment: Added below! ########## docs/branching-and-tagging.md: ########## @@ -0,0 +1,82 @@ +--- +title: "Branching and Tagging" +url: branching +aliases: + - "tables/branching" +menu: + main: + parent: Tables + weight: 0 +--- + +<!-- + - 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. + --> + +# Branching and Tagging + +## Overview + +Iceberg table metadata maintains a log of snapshots which represent the changes applied to a table. +Snapshots are fundamental in Iceberg as they are the basis for reader isolation and time travel queries. +For controlling metadata size and storage costs, Iceberg provides snapshot lifecycle management procedures such as [`expire_snapshots`](../../spark/spark-procedures/#expire-snapshots) for removing unused snapshots and no longer neccessary data files based on table snapshot retention properties. + +**For more sophisticated snapshot lifecycle management, Iceberg also supports branches and tags which are named references to snapshots.** Branches are independent lineages of snapshots and point to the head of the lineage. +Branches and tags have independent lifecycles with regards to snapshot retention during `expireSnapshots`. + +Branching and tagging can be used for handling GDPR requirements and retaining important historical snapshots for auditing. +Branches can also be used as part of data engineering workflows, for enabling experimental branches for testing and validating new jobs. +See below for some examples of how branching and tagging can facilitate these use cases. + + + +The above diagram shows an example of using tag to retain historical snapshots. +In this case a end of year tag is created for the final snapshot in the year, and the tagged snapshot has a retention of 5 years for compliance reasons. + + Review Comment: Done! -- This is an automated message from the Apache Git Service. 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