To support PG compliant SQL DML statement

[RogueJin]

Development Task

Description

Since TiDB is Mysql compliant database, we need to adjust DCParser yacc paser files to remove mysql keywords and add pg keywords, and then implement the keywords logic functions in TiDB4PG project.

Task List

DCParser:

Please check the issue:
DigitalChinaOpenSource/DCParser#21

TiDB4PG

Keywords Implement

• Returning Keyword