Fix (issuse: #104) : Cast error when 'set password'

[joeCarf]

Problems solved in this PR

issuse: #104

Changes proposed in this PR

Tests

• Unit test
• DML_DDL test

Release note

None

[joeCarf]

@Oldbread3 PTAL:)

[Oldbread3]

Will this fix cause exception for statement like set password for yejr@'%' = password('xx'); ?

[Oldbread3]

Amend use name at code path below might be the proper way to fix this issue.

polardbx-sql/polardbx-parser/src/main/java/com/alibaba/polardbx/druid/sql/dialect/mysql/parser/MySqlStatementParser.java

Line 6506 in ffd596b

user = this.exprParser.name();

[joeCarf]

Amend use name at code path below might be the proper way to fix this issue.

polardbx-sql/polardbx-parser/src/main/java/com/alibaba/polardbx/druid/sql/dialect/mysql/parser/MySqlStatementParser.java

Line 6506 in ffd596b

user = this.exprParser.name();

when using statement set password for yejr@'%' = password('xx');, variable user is a MySqlUserName object, while using set password for yejr = password('xx'); statement, user is a SQLIdentifierExpr object.

should i just cast SQLIdentifierExpr to MySqlUserName in MysqlStatementParser.class (code path above) or or use if sentense just in code path below ?

polardbx-sql/polardbx-server/src/main/java/com/alibaba/polardbx/server/handler/privileges/polar/PolarSetPasswordHandler.java

Line 77 in 55ca0c9

MySqlUserName userName = (MySqlUserName) assignItem.getTarget();

[joeCarf]

I think this might be a more safe way to fix this issue, cause it did't change parseSet() function in MysqlStatementParser, and won't affect other using scenario. PTAL:) @Oldbread3

[ZSYTY]

LGTM

[ZSYTY]

LGTM

[joeCarf]

这个pr还不能合入嘛 @Oldbread3 @ZSYTY