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Kirill Tkalenko commented on IGNITE-18733: ------------------------------------------ Should fix fluky *org.apache.ignite.internal.sql.engine.ItDmlTest#pkConstraintConsistencyTest* > Mechanism to synchronize database schema changes between nodes > -------------------------------------------------------------- > > Key: IGNITE-18733 > URL: https://issues.apache.org/jira/browse/IGNITE-18733 > Project: Ignite > Issue Type: Epic > Components: persistence > Reporter: Sergey Chugunov > Priority: Major > Labels: ignite-3 > > Usability of Apache Ignite as a distributed database to a large extent > depends on a solid support of dynamic schema changes. > DDL operations like adding of deleting columns of a table or (more > importantly) adding or dropping indexes require proper syncronization between > nodes and integration with a number of other components. > Regardless of implementation details synchronization mechanism: > * should allow (most) user operations and schema change operations to > execute concurrently; > * should allow access to the data despite of the version of its schema; > * should shorten periods of time when certain types of operations are > suspended or work ineffectively (e.g. because of rebuilding of an index). > Schema synchronization needs integration with the following components (the > list may not be exhaustive): > * SQL engine - provide information about start and stop of operations, > notify about [un]availability of certain indexes; > * TX engine - e.g. if a transaction is started concurrently with DDL > operations; > * GC for MV storages - garbage collector needs to be aware of schema changes. -- This message was sent by Atlassian Jira (v8.20.10#820010)