[IGNITE-19226] Fetch table schema by timestamp

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Labels: iep-98 ignite-3
• Epic Link: Schema synchronization
• Assignee: Roman Puchkovskiy
• Reporter: Roman Puchkovskiy
• Reviewer: Kirill Tkalenko
• Created: 05/Apr/23 08:03
• Updated: 14/Oct/23 06:39
• Resolved: 12/Oct/23 14:03

Description

Currently, when obtaining a schema, its latest (from the local point of view) version is returned.

1. Table schema must always be obtained using a timestamp
2. This might require a wait (until MetaStorage's SafeTime >= schemaTs-DD, see https://cwiki.apache.org/confluence/display/IGNITE/IEP-98%3A+Schema+Synchronization#IEP98:SchemaSynchronization-Waitingforsafetimeinthepast )

This includes the mechanisms that allow clients obtain 'current' schema (like 'DESCRIBE <table>', 'list tables', etc).

Issue Links

• fixes: IGNITE-18449 Select from a table fails after the table is created
• fixes: IGNITE-17931 Blocking code inside SchemaRegistryImpl#schema(int), need to be refactored.
• relates to: IGNITE-20633 Remove QueryStartRequest#schemaVersion()
• relates to: IGNITE-17931 Blocking code inside SchemaRegistryImpl#schema(int), need to be refactored.
• split to: IGNITE-20518 Use CatalogService in JdbcMetadataCatalog
• split to: IGNITE-20520 Specify schema version when getting table before query execution
• split to: IGNITE-20537 Add ability to create implicit transactions
• split to: IGNITE-20588 Use consistent schema when converting data in KV/record views
• split to: IGNITE-20590 Remove TxManager.beginImplicit()
• links to: GitHub Pull Request #2648