mysql 多次查询临时表_mysql中如何多次使用from子查询形成的临时表

select * from (select news.*,@num:=@num+1 as num from news,(select @num:=0) as t order by updatetime desc) as tmp where num=(select num from tmp where id=5)-1;

结果报错,tmp表不存在

谢谢诸位了

附:

创建及插入数据的sql

create table news(

id int unsigned primary key auto_increment,

title varchar(50) not null default '',

inputtime int unsigned not null default 0,

updatetime int unsigned not null default 0

)engine myisam charset utf8;

insert into news

values

(null,'第一篇文章',1240902890,1240902890),

(null,'第二篇文章',1241422082,1241422082),

(null,'第三篇文章',1241422402,1241422402),

(null,'第四篇文章',1241422518,1241422518),

(null,'第五篇文章',1241422573,1241422573),

(null,'第六篇文章',1241422785,1241422785),

(null,'第七篇文章',1241425512,1241425512),

(null,'第八篇文章',1241511871,1241511871),

(null,'第九篇文章',1241966951,1241966951);

后面的子查询 select num from tmp where id=5 ,tmp不存在。两个属于平级子查询,后面的的子查询不能用之前的tmp。可以把 后面的子查询条件 写在前面的子查询里。

可以在ng-repeat中加入过滤器,把第一个下啦作为第二个过滤条件写法上就不对,逻辑不清晰,可以把字查询和主表以id建立关联

mysql并不支持with as 的写法,但是可以使用子查询替代:

select tmp.*

from

(

select news.*,@num:=@num+1 as num

from news,(select @num:=0)

as t order by updatetime desc

) as tmp

where tmp.num=

— 这句和你的原语句的where一致

(select num-1 from

(select news.*,@num_t:=@num_t+1 as num

from news,(select @num_t:=0)

as t order by updatetime desc)t where id=5)


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