create table t1(id int,name varchar2(10));
insert into t1 values(1,'aaa');
insert into t1 values(2,'bbb');
insert into t1 values(3,'ccc');
insert into t1 values(4,'ddd');
insert into t1 values(5,'eee');
commit;
create table t1_a as select * from t1 where 1=2;
create table t1_b as select * from t1 where 1=2;
无条件多表插入：
insert all into t1_a into t1_b select * from t1;
有条件多表插入：
insert all when id<3 then into t1_a else into t1_b select * from t1;
优先插入：
insert first when id<3 then into t1_a when id>1 then into t1_b select * from t1;
旋转插入：行列转换
create table sales(id number,name varchar2(10),q1 number,q2 number,q3 number,q4 number);
insert into sales values(1,'apple',1000,2000,3000,4000);
insert into sales values(2,'orange',2000,2000,4000,4000);
insert into sales values(3,'grape',1500,2000,3600,4000);
insert into sales values(4,'banana',1900,2000,3900,4000);
commit;
create table sales_info(id number,name varchar2(10),quarter varchar2(5),smount number);
insert all
into sales_info values(id,name,'q1',q1)
into sales_info values(id,name,'q2',q2)
into sales_info values(id,name,'q3',q3)
into sales_info values(id,name,'q4',q4)
select id,name,q1,q2,q3,q4 from sales;
列转行：
select * from ((select id,name,smount,quarter from sales_info) pivot(sum(smount) for quarter in ('q1' as q1,'q2' as q2,'q3' as q3,'q4' as q4)))
SELECT 非聚合列
FROM 源表或子查询
PIVOT (
聚合函数(待聚合列) -- 对数据进行聚合（如SUM、COUNT、AVG等）
FOR 行转列的基准列 -- 指定哪一列的取值将转换为新列
IN (值1 AS 列名1, 值2 AS 列名2, ...) -- 明确要转换为列的具体值及对应列名
);
with 子句：
WITH aaaa AS (SELECT * FROM "SYSIBM".SYSDUMMY1 s), bbbb AS (SELECT * FROM aaaa) SELECT * FROM bbbb;
分页查询公式：
分页查询起始行=（页码 - 1）*每页长度 + 1
分页查询中止行= 页码*每页长度
跳过前5行，取后面5行：（12C才有的功能）
select * from jk order by sn offset 5 rows fetch next 5 rows only;
前10%的记录：
select * from jk order by sal desc fetch first 10 percent rows only;
如果有并行的值，也要显示出来（即使超出了实际规定的百分比）
select * from jk order by sal desc fetch first 10 percent rows with ties;
如果不喜欢自己换算时间，则用timestamp with local time zone 会将用户输入的时间转换为数据库服务器所在时区的时间
如果喜欢保存原本的时区信息，则用timestamp with time zone
create table meeting(name varchar2(10),
time1 timestame,
time2 timestamp with time zone,
time3 timestame with local time zone);