SQL MODE

SQL MODE enables users to switch between different styles of SQL syntax and data verification strictness, making Doris more compatible with other databases. For example, in some databases, the ‘||’ symbol is a string connector, but in Doris it is equivalent to ‘or’. At this time, users only need to use SQL mode to switch to the style they want. Each client can set sql mode, which is valid in the current conversation. Only users with admin permission can set global SQL mode.

SQL MODE is stored in session variables with a 64 bit long type. Each bit of this address represents the on / off (1 for on, 0 for off) state of a mode. As long as we know the specific bit of each mode, we can easily and quickly verify and operate SQL mode through bit operation.

Every time you query sql mode, the long type will be parsed into a user-readable string. Similarly, the sql mode string sent by the user to the server will be parsed into a long type that can be stored in session variables.

1、set sql mode

2、select sql mode

(Work in progress)