SQL大全－－－－－－之 oracle关于insert all的用法

INSERT FIRST
同时插入到多张表，在这里整理下，以供查阅。先建两个测试表，ww1，ww2
SQL> desc ww1
名称 是否为空? 类型
----------------------------------------- -------- ---------------
ID NUMBER
NAME VARCHAR2(30)
SQL> desc ww2
名称 是否为空? 类型
----------------------------------------- -------- ---------------
ID NUMBER
NAME VARCHAR2(30)
TABLESPACENAME VARCHAR2(30)
无条件INSERT，同时向这两表插入数据
insert all
into ww1 values( object_id,object_name)
into ww2 values(object_id,object_name,object_type)
select objecT_id,object_name,object_type
from user_objects
where rownum<20
/
已创建38行。
SQL> select count(*) from ww1;
COUNT(*)
----------
19
可以看到总共插入了38行，每个表插入了19行
条件INSERT，当每个不同条件成立的时候插入不同表
insert all
when object_type='TABLE' then into ww1 values (object_id,object_name)
when object_type='SYNONYM' then into ww2 values (objecT_id,object_name,object_type)
select object_id,object_name,object_type
from user_objects
/
已创建727行。
SQL> select count(*) from ww1;
COUNT(*)
----------
718
SQL> select count(*) from ww2;
COUNT(*)
----------
9
可以看到，符合object_type='TABLE'的718条记录被插入到ww1表中，符合object_type='SYNONYM'的9条记录被插入到ww2表中，总共插入了718条记录。
条件FIRST INSERT
1 select objecT_id ,object_type from user_objects
2* where object_id<10
3 /
OBJECT_ID OBJECT_TYPE
---------- --------------------------------------
2 CLUSTER
3 INDEX
4 TABLE
5 TABLE
6 CLUSTER
7 INDEX
8 CLUSTER
9 INDEX
看到前9条记录中,INDEX 有4条.于是写如下SQL测试
insert first
when object_type='INDEX' then into ww values (object_id)
when object_id<10 then into ww1 values (object_id,object_name)
select object_id,object_name,object_type
from user_objects
/
已创建715行。
SQL> select count(*) from ww;
COUNT(*)
----------
710
SQL> select * from ww1;
ID NAME
---------- ---------------------
6 C_TS#
5 CLU$
8 C_FILE#_BLOCK#
2 C_OBJ#
4 TAB$
可以看到,用FIRST后,凡是符合第一个条件的就都插入第一个表,其他的数据才再以后的条件里再判断.
用这种写法,也可以达到行转列的目的.
TINSERT ALL
INTO sales_info VALUES (employee_id,week_id,sales_MON)
INTO sales_info VALUES (employee_id,week_id,sales_TUE)
INTO sales_info VALUES (employee_id,week_id,sales_WED)
INTO sales_info VALUES (employee_id,week_id,sales_THUR)
INTO sales_info VALUES (employee_id,week_id, sales_FRI)
SELECT EMPLOYEE_ID, week_id, sales_MON, sales_TUE,sales_WED, sales_THUR,sales_FRI
FROM sales_source_data;