explain results show stats:pseudo in operator info though it uses true stats

[xuyifangreeneyes]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

use test;
drop table if exists t;
create table t(a int primary key, b int, c int, index idx_b(b));
insert into t values (1,2,3), (4,5,6), (7,8,9), (10, 11, 12), (13,14,15), (16, 17, 18);
analyze table t;
explain format = 'brief' select * from t use index (idx_b) where b = 2 limit 1;

2. What did you expect to see? (Required)

mysql> explain format = 'brief' select * from t use index (idx_b) where b = 2 limit 1;
+-----------------------------+---------+-----------+-------------------------+-----------------------------------+
| id                          | estRows | task      | access object           | operator info                     |
+-----------------------------+---------+-----------+-------------------------+-----------------------------------+
| IndexLookUp                 | 1.00    | root      |                         | limit embedded(offset:0, count:1) |
| ├─Limit(Build)              | 1.00    | cop[tikv] |                         | offset:0, count:1                 |
| │ └─IndexRangeScan          | 1.00    | cop[tikv] | table:t, index:idx_b(b) | range:[2,2], keep order:false     |
| └─TableRowIDScan(Probe)     | 1.00    | cop[tikv] | table:t                 | keep order:false                  |
+-----------------------------+---------+-----------+-------------------------+-----------------------------------+
4 rows in set (0.01 sec)

3. What did you see instead (Required)

mysql> explain format = 'brief' select * from t use index (idx_b) where b = 2 limit 1;
+-----------------------------+---------+-----------+-------------------------+-----------------------------------+
| id                          | estRows | task      | access object           | operator info                     |
+-----------------------------+---------+-----------+-------------------------+-----------------------------------+
| IndexLookUp                 | 1.00    | root      |                         | limit embedded(offset:0, count:1) |
| ├─Limit(Build)              | 1.00    | cop[tikv] |                         | offset:0, count:1                 |
| │ └─IndexRangeScan          | 1.00    | cop[tikv] | table:t, index:idx_b(b) | range:[2,2], keep order:false     |
| └─TableRowIDScan(Probe)     | 1.00    | cop[tikv] | table:t                 | keep order:false, stats:pseudo    |
+-----------------------------+---------+-----------+-------------------------+-----------------------------------+
4 rows in set (0.01 sec)

4. What is your TiDB version? (Required)

mysql> SELECT tidb_version();
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| tidb_version()                                                                                                                                                                                                                                |
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Release Version: None
Edition: Community
Git Commit Hash: None
Git Branch: None
UTC Build Time: None
GoVersion: go1.16.4
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false |
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

[xuyifangreeneyes]

/sig planner

[xuyifangreeneyes]

/assign

[ti-srebot]

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