同时在a表和b表中生成一条数据的sql语句的建立方法

如何建立一条sql语句使在a表中生成一条数据同时b表也生成一条

使用循环语句，可以插入任意的数据。

参考代码：

delete from whilestu1;

commit;

DECLARE

num1 number;

maxstuid number;

age number;

birthday date;

begin

num1:=1;

WHILE num1--获取最大的stuid

select max(stuid)+1 into maxstuid from whilestu1;

if maxstuid is null then

maxstuid:=1;

end if;

birthday:=sysdate-ROUND(DBMS_RANDOM.VALUE(300,600),0);

age:=ROUND(DBMS_RANDOM.VALUE(18,40),0);

--插入数据

insert into whilestu1(stuid,stuName,age,birthday)

values (maxstuid，'学员'||cast(maxstuid as varchar2(50)),age,birthday);

commit;

num1:=num1+1;

END LOOP;

end;

/

SQL在查询结果中选取某一条数据

-- 用的啥数据库也不写清楚。。。

-- MS sql server2005以上，ORACLE

select * from (

select row_number() over ( order by starttime asc) as rownum,* from steriworkrecord where starttime between '2013-11-1' and '2013-12-31'

) a

where rownum between 2 and 10-- 【注意（ order by starttime asc）是你排序的方式asc升序，desc降序】

========================================================

-- ORACLE还可以

select * from (

select rownum as n,* from steriworkrecord

where starttime between '2013-11-1' and '2013-12-31'

) a

where a.n between 2 and 10==========================================================

-- MYSQL,postgreSQL似乎只能标量子查询

SELECT *FROM (

SELECT a.*,(

SELECT count(*) FROM steriworkrecordb WHERE b.ID<= a.ID) AS n

from steriworkrecorda

) ts

where ts.n between 2 and 10

-- 【注意b.ID<= a.ID 其中ID换成你的主键名称】

-- 代码都忙你实际测试了ok

如何用SQL语句取出数据库中的特定一条数据

通过查询语句select * from user where id=1

我不知道你这个username指的是不是字段，如果是要取出表中某个字段的值。

可以通过select 字段名1，字段名2 ... from user where id=1。

-- MS sql server2005以上，ORACLE

select * from (

select row_number() over ( order by starttime asc) as rownum,* from steriworkrecord

where starttime between '2013-11-1' and '2013-12-31'

) a

where rownum between 2 and 10

-- 【注意（ order by starttime asc）是你排序的方式asc升序，desc降序】

-- ORACLE还可以

select * from (

select rownum as n,* from steriworkrecord

where starttime between '2013-11-1' and '2013-12-31'

) a

where a.n between 2 and 10

-- MYSQL,postgreSQL似乎只能标量子查询

SELECT *FROM (

SELECT a.*,(

SELECT count(*) FROM steriworkrecordb WHERE b.ID<= a.ID) AS n

from steriworkrecorda

) ts

where ts.n between 2 and 10

-- 【注意b.ID<= a.ID 其中ID换成你的主键名称】