一点示例明白mysql存储过程

</pre></div><div style="font-family: 'Microsoft YaHei UI', 'Microsoft YaHei', SimSun, 'Segoe UI', Tahoma, Helvetica, sans-serif, 'Microsoft YaHei', Georgia, Helvetica, Arial, sans-serif, 宋体, PMingLiU, serif; line-height: 21px;"><span style="font-size:18px;"><span style="font-family: 'Microsoft YaHei UI', 'Microsoft YaHei', SimSun, 'Segoe UI', Tahoma, Helvetica, sans-serif, 'Microsoft YaHei', Georgia, Helvetica, Arial, sans-serif, 宋体, PMingLiU, serif; line-height: 37.894737243652344px;">封装sql：</span></span><!--EndFragment--></div><div style="font-family: 'Microsoft YaHei UI', 'Microsoft YaHei', SimSun, 'Segoe UI', Tahoma, Helvetica, sans-serif, 'Microsoft YaHei', Georgia, Helvetica, Arial, sans-serif, 宋体, PMingLiU, serif; line-height: 21px;"><span style="font-size:18px;"><span style="font-family: 'Microsoft YaHei UI', 'Microsoft YaHei', SimSun, 'Segoe UI', Tahoma, Helvetica, sans-serif, 'Microsoft YaHei', Georgia, Helvetica, Arial, sans-serif, 宋体, PMingLiU, serif; line-height: 37.894737243652344px;"></span></span><pre name="code" class="sql">create procedure p1()
begin
select  * from t_news;
end $         //mysql存储过程 简单实例

<span style="font-size:18px;">create procedure p2(n int)    #含参
begin
select  * from t_category where cid > n;
end $   </span>   

<span style="font-size:18px;">create procedure p3(n int, j char(1))    #含参
begin  
if j='h'  then       #与其他语言不同 必须加then 注意符号= 不是==
 select  * from t_category where cid > n;
else
select  * from t_category where cid <n;   
end if;
end $      </span>

create procedure p4(n smallint)    #含参
begin  
declare  i int;
declare s int;
set s = 0;
set i = 1;
while i<=n do
set s =s+i;
set i=i+1;
end while;
select s;
end $      

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