[Bug]: set global tx_isolation=4 panic error

[heni02]

Is there an existing issue for the same bug?

• I have checked the existing issues.

Branch Name

main

Commit ID

52b7c7b

Other Environment Information

- Hardware parameters:
- OS type:
- Others:

Actual Behavior

set global tx_isolation = 4 panic报错，确认下=5时是否符合预期？ tx_isolation取值范围时多少？
mysql> set global tx_isolation = 2;
Query OK, 0 rows affected (0.03 sec)

mysql> show global variables like 'tx_isolation';
+---------------+-----------------+
| Variable_name | Value |
+---------------+-----------------+
| tx_isolation | REPEATABLE-READ |
+---------------+-----------------+
1 row in set (0.00 sec)

mysql> set global tx_isolation = 3;
Query OK, 0 rows affected (0.02 sec)

mysql> show global variables like 'tx_isolation';
+---------------+--------------+
| Variable_name | Value |
+---------------+--------------+
| tx_isolation | SERIALIZABLE |
+---------------+--------------+
1 row in set (0.00 sec)

mysql> set global tx_isolation = 4;
ERROR 20101 (HY000): internal error: panic runtime error: index out of range [4] with length 4:
runtime.goPanicIndex
/Users/heni/go/pkg/mod/golang.org/[e-mail]-arm64/src/runtime/panic.go:114
github.com/matrixorigin/matrixone/pkg/frontend.SystemVariableEnumType.Convert.func1
/Users/heni/test-envir/matrixone/pkg/frontend/variables.go:600
github.com/matrixorigin/matrixone/pkg/frontend.SystemVariableEnumType.Convert
/Users/heni/test-envir/matrixone/pkg/frontend/variables.go:631
github.com/matrixorigin/m
mysql> set global tx_isolation = 5;
ERROR 20101 (HY000): internal error: convert to the system variable enum type failed

Expected Behavior

No response

Steps to Reproduce

set global tx_isolation = 4;

Additional information

No response

[Kai Cao]

确认下=5时是否符合预期？ 符合预期
tx_isolation取值范围时多少？0-3，分别对应"READ-UNCOMMITTED", "READ-COMMITTED", "REPEATABLE-READ", "SERIALIZABLE"

set global tx_isolation = 4 panic报错原因是合法值判断有问题。

[heni02]

另外一个问题：set global TIME_ZONE查询结果是system，但set session TIME_ZONE查询结果是修改后的值
SET global TIME_ZONE='+08:00';
select @@TIME_ZONE;
@@TIME_ZONE
SYSTEM

SET TIME_ZONE='+08:00';
select @@TIME_ZONE;
@@TIME_ZONE
+08:00

[Kai Cao]

另外一个问题：set global TIME_ZONE查询结果是system，但set session TIME_ZONE查询结果是修改后的值 SET global TIME_ZONE='+08:00'; select @@TIME_ZONE; @@TIME_ZONE SYSTEM

SET TIME_ZONE='+08:00'; select @@TIME_ZONE; @@TIME_ZONE +08:00

这是refactor之后的期望行为，set global只影响global级别，不会修改session级别的值，具体可参考文档：https://doc.weixin.qq.com/doc/w3_AVIAugbFALcLhtRyzyDQZqwLQ0OiE?scode=AJsA6gc3AA8iTL8CYi

[heni02]

confirm,closed
commit:3e36439cf387571c341d8dc971f47acb9cc12dde
mysql> set global tx_isolation = 4;
ERROR 20101 (HY000): internal error: convert to the system variable enum type failed