[FLINK-20562] Support ExplainDetails for EXPLAIN sytnax

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.14.0
• Component/s: Table SQL / API
• Labels: pull-request-available sprint
• Assignee: WeiNan Zhao
• Reporter: Jark Wu
• Created: 10/Dec/20 09:52
• Updated: 21/Jul/21 10:42
• Resolved: 21/Jul/21 10:42

Description

Currently, EXPLAIN syntax only supports to print the default AST, logical plan, and physical plan. However, it doesn't support to print detailed information such as CHANGELOG_MODE, ESTIMATED_COST, JSON_EXECUTION_PLAN which are defined in ExplainDetail.

Allow users to specify the ExplainDetails in statement.

EXPLAIN [ExplainDetail[, ExplainDetail]*] <statement>



ExplainDetail: {

  ESTIMATED_COST,

  CHANGELOG_MODE,

  JSON_EXECUTION_PLAN

}

Print the plan for the statement with specified ExplainDetails.

ESTIMATED_COST
generates cost information on physical node estimated by optimizer, e.g. TableSourceScan(..., cumulative cost =

{1.0E8 rows, 1.0E8 cpu, 2.4E9 io, 0.0 network, 0.0 memory}

)

CHANGELOG_MODE
generates changelog mode for every physical rel node. e.g. GroupAggregate(..., changelogMode=[I,UA,D])

JSON_EXECUTION_PLAN
generates the execution plan in json format of the program.

Flink SQL> EXPLAIN ESTIMATED_COST, CHANGELOG SELECT * FROM MyTable;
...

Issue Links

• duplicates: FLINK-21465 Extend explain syntax
• links to: GitHub Pull Request #15317