tidb oom because of infinite loop

[ChenPeng2013]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

pk_snpre10114 only have 103 rows, but TableRangeScan operator actRows is 16002212

MySQL [coms]> select count(*) from pk_snpre10114;
+----------+
| count(*) |
+----------+
|      103 |
+----------+
1 row in set (0.00 sec)

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

3. What did you see instead (Required)

MySQL [coms]> explain for connection 2281598777821235421;
+------------------------------+---------+----------+-----------+---------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------+------+
| id                           | estRows | actRows  | task      | access object       | execution info                                                                                                                                                                                                                                                                                                              | operator info                                                                                                                                                                                                                                                                                       | memory | disk |
+------------------------------+---------+----------+-----------+---------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------+------+
| Projection_4                 | 0.00    | 0        | root      |                     | time:0s, loops:0                                                                                                                                                                                                                                                                                                            | coms.pk_snpre10114.col2                                                                                                                                                                                                                                                                             | N/A    | N/A  |
| └─Selection_8                | 0.00    | 0        | root      |                     | time:0s, loops:0                                                                                                                                                                                                                                                                                                            | in(coms.pk_snpre10114.col1, "0x61219f79c90d3541f70e", 5501707547099269248, "0xec43efd30131dea2cb8b"), or(isnull(coms.pk_snpre10114.col2), in(coms.pk_snpre10114.col2, "呣丼蒢咿卻鹻铴础湜僂頃dž縍套衞陀碵碼幓9", "鹹楞睕堚尛鉌翡佾搁紟精廬姆燵藝潐楻翇慸嵊"))                                        | N/A    | N/A  |
|   └─TableReader_7            | 0.00    | 0        | root      |                     | time:0s, loops:0, cop_task: {num: 7990466, max: 223.8ms, min: 168.2µs, avg: 793.6µs, p95: 2.47ms, max_proc_keys: 2, p95_proc_keys: 0, tot_proc: 27.3s, tot_wait: 3m57.8s, rpc_num: 7992372, rpc_time: 1h43m57.7s, copr_cache_hit_ratio: 0.96, distsql_concurrency: 15}, backoff{regionMiss: 1.01s, regionScheduling: 6ms}   | data:Selection_6                                                                                                                                                                                                                                                                                    | N/A    | N/A  |
|     └─Selection_6            | 0.00    | 0        | cop[tikv] |                     | tikv_task:{proc max:4ms, min:0s, avg: 2.62ms, p80:3ms, p95:4ms, iters:7997090, tasks:7997090}, scan_detail: {total_process_keys: 661848, total_process_keys_size: 90673176, total_keys: 1654620, get_snapshot_time: 1m3.5s, rocksdb: {key_skipped_count: 661848, block: {cache_hit_count: 1985544}}}                        | or(isnull(coms.pk_snpre10114.col2), in(coms.pk_snpre10114.col2, "呣丼蒢咿卻鹻铴础湜僂頃dž縍套衞陀碵碼幓9", "鹹楞睕堚尛鉌翡佾搁紟精廬姆燵藝潐楻翇慸嵊"))                                                                                                                                              | N/A    | N/A  |
|       └─TableRangeScan_5     | 2.00    | 16002212 | cop[tikv] | table:PK_SNPRE10114 | tikv_task:{proc max:4ms, min:0s, avg: 2.62ms, p80:3ms, p95:4ms, iters:7998953, tasks:7998953}                                                                                                                                                                                                                               | range:[0x61219F79C90D3541F70E,0x61219F79C90D3541F70E], [0xEC43EFD30131DEA2CB8B,0xEC43EFD30131DEA2CB8B], [0x35353031373037353437303939323639323438,0x35353031373037353437303939323639323438], keep order:false, stats:pseudo                                                                         | N/A    | N/A  |
+------------------------------+---------+----------+-----------+---------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------+------+
5 rows in set (5.55 sec)

4. What is your TiDB version? (Required)

| Release Version: v6.2.0
Edition: Community
Git Commit Hash: a399181d861e21a1dbfc3ed00228866a1acd02c9
Git Branch: heads/refs/tags/v6.2.0
UTC Build Time: 2022-07-30 10:09:58
GoVersion: go1.18.2
Race Enabled: false
TiKV Min Version: 6.2.0-alpha
Check Table Before Drop: false
Store: tikv |

[tiancaiamao]

Could you find the SQL that trigger this? @ChenPeng2013

[ChenPeng2013]

reproduce step

use test;
source [test.txt](https://github.com/pingcap/tidb/files/9256389/test.txt);
prepare stmt from 'SELECT * FROM PK_SNPRE10114 WHERE col1 IN (?, ?, ?) AND (col2 IS NULL OR col2 IN (?, ?)) AND (col3 IS NULL OR col4 IS NULL);';
set @a=0x0D5BDAEB79074756F203, @b=NULL, @c=0x6A911AAAC728F1ED3B4F, @d="鏖秿垙麜濇凗辯Ũ卮伄幖轒ƀ漭蝏雓轊恿磔徵", @e="訇廵纹髺釖寒近槩靏詗膦潳陒錃粓悧闒摔)乀";
execute stmt using @a,@b,@c,@d,@e;
set @a=7775448739068993371, @b=5641728652098016210, @c=6774432238941172824, @d="HqpP5rN", @e="8Fy";
execute stmt using @a,@b,@c,@d,@e;
set @a=0x61219F79C90D3541F70E, @b=5501707547099269248, @c=0xEC43EFD30131DEA2CB8B, @d="呣丼蒢咿卻鹻铴础湜僂頃dž縍套衞陀碵碼幓9", @e="鹹楞睕堚尛鉌翡佾搁紟精廬姆燵藝潐楻翇慸嵊";
execute stmt using @a,@b,@c,@d,@e;

| Release Version: v6.2.0-alpha-607-g5ef1898
Edition: Community
Git Commit Hash: 5ef18981ccc2173120c5e85d3c57abc17f255d2f
Git Branch: master
UTC Build Time: 2022-08-04 03:13:05
GoVersion: go1.18.2
Race Enabled: false
TiKV Min Version: 6.2.0-alpha
Check Table Before Drop: false
Store: unistore |

[zhaoxinyu]

Maybe the dead loop in title should be replaced with infinite loop. @ChenPeng2013