mysql 5.0存储过程学习总结
mysql存储过程学习总结-操作符 算术运算符 加 SET var1=22; 4 - 减 SET var2=3-2; 1 *乘 SET var3=3*2; 6 / 除 SET var4=10/3; 3.3333 DIV 整除SET var5=10 DIV 3; 3 % 取模SET var6=10%3 ; 1 比较运算符 大于12False 小于21False = 小于等于2=2True = 大于
mysql存储过程学习总结-操作符
算术运算符
+ 加 SET var1=2+2; 4
- 减 SET var2=3-2; 1
* 乘 SET var3=3*2; 6
/ 除 SET var4=10/3; 3.3333
DIV 整除 SET var5=10 DIV 3; 3
% 取模 SET var6=10%3 ; 1
比较运算符
> 大于 1>2 False
>= 大于等于 3>=2 True
BETWEEN 在两值之间 5 BETWEEN 1 AND 10 True
NOT BETWEEN 不在两值之间 5 NOT BETWEEN 1 AND 10 False
IN 在集合中 5 IN (1,2,3,4) False
NOT IN 不在集合中 5 NOT IN (1,2,3,4) True
= 等于 2=3 False
, != 不等于 23 False
严格比较两个NULL值是否相等 NULLNULL True
LIKE 简单模式匹配 "Guy Harrison" LIKE "Guy%" True
REGEXP 正则式匹配 "Guy Harrison" REGEXP "[Gg]reg" False
IS NULL 为空 0 IS NULL False
IS NOT NULL 不为空 0 IS NOT NULL True
逻辑运算符
与(AND)
AND |
TRUE |
FALSE |
NULL |
---|---|---|---|
TRUE |
TRUE |
FALSE |
NULL |
FALSE |
FALSE |
FALSE |
NULL |
NULL |
NULL |
NULL |
NULL |
或(OR)
OR |
TRUE |
FALSE |
NULL |
---|---|---|---|
TRUE |
TRUE |
TRUE |
TRUE |
FALSE |
TRUE |
FALSE |
NULL |
NULL |
TRUE |
NULL |
NULL |
异或(XOR)
XOR |
TRUE |
FALSE |
NULL |
---|---|---|---|
TRUE |
FALSE |
TRUE |
NULL |
FALSE |
TRUE |
FALSE |
NULL |
NULL |
NULL |
NULL |
NULL |
位运算符
| 位或
& 位与
>> 右移位
~ 位非(单目运算,按位取反)

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