[FLINK-39957][table] Support EXPLAIN of CREATE [OR ALTER] MATERIALIZED TABLE#28510
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raminqaf wants to merge 5 commits into
Open
[FLINK-39957][table] Support EXPLAIN of CREATE [OR ALTER] MATERIALIZED TABLE#28510raminqaf wants to merge 5 commits into
raminqaf wants to merge 5 commits into
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…LE in the SQL parser
…translatable as ModifyOperation
…R to a sink RelNode for EXPLAIN
… manager and add EXPLAIN ITs
…-table conversion
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snuyanzin
reviewed
Jun 22, 2026
| throw new SqlExecutionException( | ||
| "No Statement Set to submit. 'END' statement should be used after 'BEGIN STATEMENT SET'."); | ||
| } else if (op instanceof ModifyOperation) { | ||
| } else if (op instanceof ModifyOperation && !(op instanceof MaterializedTableOperation)) { |
Contributor
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is there a reason MaterializedTableOperation is not a ModifyOperation
however after that we call callModifyOperations ?
snuyanzin
reviewed
Jun 22, 2026
| assertThat( | ||
| service.getTable(sessionHandle, getObjectIdentifier("users_shops")) | ||
| .getTableKind()) | ||
| .isSameAs(CatalogBaseTable.TableKind.TABLE); |
Contributor
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use static import if it requires more than 2 names
snuyanzin
reviewed
Jun 22, 2026
| * golden resource. The per-test catalog name is normalized to {@code $CATALOG} before | ||
| * comparison. | ||
| */ | ||
| static void verifyExplainPlan( |
Contributor
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why do we need to create another plan verifier if there is already existing framework for this?
See TableTestBase
snuyanzin
reviewed
Jun 22, 2026
Comment on lines
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| public static PlannerQueryOperation validateAndConvertAsQuery( | ||
| SqlNode asQuery, ConvertContext context) { | ||
| final FlinkPlannerImpl flinkPlanner = context.getFlinkPlanner(); | ||
| final SqlNode validated = flinkPlanner.validate(asQuery); | ||
| final Operation operation = | ||
| SqlNodeToOperationConversion.convert( | ||
| flinkPlanner, context.getCatalogManager(), validated) | ||
| .orElseThrow( | ||
| () -> | ||
| new TableException( |
Contributor
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method has pretty generic name, then somewhere in the middle it throws
"Unsupported materialized table definition query: "
either make it generic or may be rename and move into. materializedTableUtils
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What is the purpose of the change
EXPLAINpreviously rejected materialized table DDL, so users had no way to inspect the plan that populates a materialized table without actually running it. This change addsEXPLAINsupport forCREATE MATERIALIZED TABLE ... AS,CREATE OR ALTER MATERIALIZED TABLE ... AS(both the alter-on-existing and the in-placetable-to-materialized-table conversion path from FLINK-39847), and
ALTER MATERIALIZED TABLE ... AS. The produced plan is the sink that writes the definition query into the materialized table, mirroring how CTAS/RTAS are explained.EXPLAINstays side-effect-free: no table is created, altered, or converted, and no refresh job is submitted.Note on scope: building the sink for a brand-new managed materialized table at
EXPLAINtime is not covered, because a managed table's storage options (e.g.path) are only assigned by the catalog at creation time. The alter and conversion paths work because they reuse the existing table's already-resolved connectoroptions. Resolving managed options at plan time without persisting is left as a follow-up.
Brief change log
CREATE/ALTER MATERIALIZED TABLEstatements afterEXPLAIN, and reject a non-ASALTERunderEXPLAINwith a clear message.ModifyOperation, carrying the validatedASquery as the sink input;ModifyOperationVisitorgains the correspondingvisitmethods.RelNodethat writes into the resulting table (reusing the existing table's resolved options for alter/convert).MaterializedTableManagerrather than the genericModifyOperationtranslation path (the newModifyOperationrole only enablesEXPLAIN, it must not change execution).Verifying this change
This change added tests and can be verified as follows:
EXPLAINofCREATE/CREATE OR ALTER/ALTER MATERIALIZED TABLE, including the rejection of a non-ASALTER.TableSinkTest) asserting the AST / optimized physical / optimized execution plans for the create and alter variants.EXPLAINplan end-to-end (against golden resources) forALTER ... AS,CREATE OR ALTERon an existing materialized table, and the table-to-materialized-table conversion, plus assertions thatEXPLAINleaves the catalog object unchanged.Does this pull request potentially affect one of the following parts:
@Public(Evolving): noDocumentation
EXPLAINsupport on the materialized table /EXPLAINstatement docs)AI-tooling disclosure
Generated cleanups by Claude Opus 4.8