mysqlwriter 中postSQL,当postSQL 很长的时候，只会执行一部分postSQL语句

example

```
"postSql": [
"RENAME TABLE sometable_bk TO sometable_new;RENAME TABLE sometable TO sometable_bk;RENAME TABLE sometable_new TO sometable_bk;RENAME TABLE sometable_abcd TO sometable_abcd_bk;"
],
```
执行的时候，会截取一部分，之后报语法错误

```
java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'RENAME TABLE
```

Start at the mysqlwriter handling of the postSql entry and reproduce the issue with the long sequence of RENAME TABLE statements shown in the report. Trace why only part of the SQL reaches MySQL; done means the complete postSql value executes without the reported syntax error.

Written by the indexing model from the issue text.