记录一些可能会用到的sql语句

记录一些SQL语句

IF…ELSE

select *,if(sva=1,"男","女") as ssva from taname where sva != ""

CASE…WHEN

update goods 

set price = ( 

case  

  when price between 0 and 99 then price * 1.2 

  when price between 100 and 999 then price * 1.1 

  when price between 1000 and 1999 then price * 1.05 

  when price > 1999 then price * 1.02 

end)

日期加减

INSERT INTO rentbookmsg VALUES ('bookname',2,'bob',3,NOW(),DATE_ADD(now(),INTERVAL 2 MONTH));

group_concat

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