任何人都可以告诉我这两个mysql运算符之间的差异： –

< =>和=

两者都得到了相同的结果.它们在使用中是否相同.

select s.dwt,s.shipnam from tbl_ship s
where s.dwt >= 1 and s.deleted = 'N'
and s.dwt = 11000
group by s.co_cod

和

select s.dwt,s.shipnam from tbl_ship s
where s.dwt >= 1 and s.deleted = 'N'
and s.dwt <=> 11000
group by s.co_cod

谢谢.