mysql怎么实现mssql的if exists() begin...end功能？

Answer 1

IF ELSE statementIF ELSE语句

IF EXISTS (SELECT 1 FROM dual WHERE 1=1) 
THEN
    #TODO
ELSE 
    #TODO
END IF;

IF ELSEIF ELSE

IF(XXXX) THEN 
    #TODO
ELSEIF(XXXXX) THEN
    #TODO
ELSEIF(XXXX) THEN
ELSE
    #TODO
END ID;

IF ELSEIF ELSE statement🎜 rrreee

Answer 2

It’s done, it turns out to be similar to mssql