json_remove is not same with MySQL

[xiekeyi98]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. What did you do?
   If possible, provide a recipe for reproducing the error.

select json_remove( '{"id": 123, "name": "systemQA", "array": [1, 2, 3]}', '$[0]' );

2. What did you expect to see?

In MySQL

mysql> select json_remove( '{"id": 123, "name": "systemQA", "array": [1, 2, 3]}', '$[0]' );
+------------------------------------------------------------------------------+
| json_remove( '{"id": 123, "name": "systemQA", "array": [1, 2, 3]}', '$[0]' ) |
+------------------------------------------------------------------------------+
| {"id": 123, "name": "systemQA", "array": [1, 2, 3]}                          |
+------------------------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> 
mysql> select version();
+-------------------------+
| version()               |
+-------------------------+
| 5.7.25-0ubuntu0.18.04.2 |
+-------------------------+
1 row in set (0.01 sec)

mysql> 

3. What did you see instead?

In TiDB

mysql> select json_remove( '{"id": 123, "name": "systemQA", "array": [1, 2, 3]}', '$[0]' );
+------------------------------------------------------------------------------+
| json_remove( '{"id": 123, "name": "systemQA", "array": [1, 2, 3]}', '$[0]' ) |
+------------------------------------------------------------------------------+
| {"array": [1, 2, 3], "id": 123, "name": "systemQA"}                          |
+------------------------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> 
mysql> select version();
+----------------------------------------+
| version()                              |
+----------------------------------------+
| 5.7.25-TiDB-v3.0.0-beta-321-gc6a757b24 |
+----------------------------------------+
1 row in set (0.00 sec)

mysql> select tidb_version()\G
*************************** 1. row ***************************
tidb_version(): Release Version: v3.0.0-beta-321-gc6a757b24
Git Commit Hash: c6a757b2435965a72ada9d61ea8b7a367bd89b5f
Git Branch: master
UTC Build Time: 2019-04-02 02:38:04
GoVersion: go version go1.12.1 linux/amd64
Race Enabled: false
TiKV Min Version: 2.1.0-alpha.1-ff3dd160846b7d1aed9079c389fc188f7f5ea13e
Check Table Before Drop: false
1 row in set (0.00 sec)

mysql> 

[erjiaqing]

Maybe this is same as #9982

[xiekeyi98]

@erjiaqing is right, close this issue.