pingcap/tidb

Change EXPLAIN operatorInfo to use ; separator

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#20,520 opened on Oct 19, 2020

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good first issuesig/plannertype/enhancement

Description

Development Task

This is a fork from the discussion in https://github.com/pingcap/tidb/pull/20482

Currently the operatorInfo is separated by ,, but since this character is commonly used in range(a,b), it would make it easier for automated programs to split based on a semicolon ;. i.e.

+------------------------------+----------+-----------+---------------+---------------------------------------------------+
| id                           | estRows  | task      | access object | operator info                                     |
+------------------------------+----------+-----------+---------------+---------------------------------------------------+
| HashJoin_17                  | 12487.50 | root      |               | inner join; equal:[eq(test.t2.t1_id, test.t1.id)] |
| ├─TableReader_20(Build)      | 9990.00  | root      |               | data:Selection_19                                 |
| │ └─Selection_19             | 9990.00  | cop[tikv] |               | not(isnull(test.t2.t1_id))                        |
| │   └─TableFullScan_18       | 10000.00 | cop[tikv] | table:t2      | keep order:false; stats:pseudo                    |
| └─TableReader_22(Probe)      | 10000.00 | root      |               | data:TableFullScan_21                             |
|   └─TableFullScan_21         | 10000.00 | cop[tikv] | table:t1      | keep order:false; stats:pseudo                    |
+------------------------------+----------+-----------+---------------+---------------------------------------------------+
6 rows in set (0.00 sec)```

Contributor guide

Tech stack
gosql
Domain
databasebackend
Issue type
refactor
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
under 1 hour
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
blocked
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
None
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
20
Research direction
The issue is to change the separator in operatorInfo from comma to semicolon in EXPLAIN output. The discussion in PR #20482 provides context. Likely files are in the execution or explain package, such as `executor/explain.go` or `util/plancodec/codec.go`. The assignee has claimed the issue, but no PR has been opened yet. The change is localized and well defined.
Change EXPLAIN operatorInfo to use ; separator · pingcap/tidb#20520 | Good First Issue