建表語句:
CREATE TABLE DIC_ORG_ADDR(
ID varchar(32) primary key NULL,
ORGAN_ID varchar(32) NULL,
ORGAN_NAME varchar(32) NULL,
ORGAN_ADDR VARCHAR(100) NULL,
TYPE CHAR(1) NULL
)插入語句:
insert into DIC_ORG_ADDR(ID,ORGAN_ID,ORGAN_NAME,ORGAN_ADDR,TYPE )
values("1","01","公安局","黑空街200號","1")
或是
insert into DIC_ORG_ADDR(ID,ORGAN_ID,ORGAN_NAME,ORGAN_ADDR,TYPE )
select * from OTHERS刪除語句:
delete from DIC_ORG_ADDR where ID='1'
刪除表語句:
drop table DIC_ORG_ADDR
修改表結構:
新增字段:
ALTER TABLE DIC_ORG_ADDR
ADD ( "valid" VARCHAR2(25) NULL )刪除字段:
ALTER TABLE DIC_ORG_ADDR
DROP ( "TYPE" ) CASCADE CONSTRAINT
GO修改數據:
update DIC_ORG_ADDR set type='0' where ID='1'
查詢語句:
select * from DIC_ORG_ADDR
創建自增長序列:
創建序列:
create sequence id_seq increment by 1 start with 1;(從1開始每次增1)
創建觸發器:(觸發器名爲trg_seq_pid ,在向DIC_ORG_ADDR表做 插入之前,
使用id_seq.nextval自增長序列,使id字段自增長。這樣插入的時候,主鍵不用輸入數據庫就會自動添加自增長的主鍵值了 )
create or replace trigger trg_seq_pid BEFORE
insert ON DIC_ORG_ADDR FOR EACH ROW
begin
select id_seq.nextval into:New.id from dual;
end trg_seq_pid ;
9. 字符串連接符:||
select name||'%' from users;
10. 截取符:trunc
select trunc(num,2) from users; 截取保留小數點後兩位,不進行四捨五入
11. case when
update users set name = (case when name='張三' then '李四' else '無名' end) where name is not null;
12. 左連接:左邊的表數據內容一定存在,右邊連接的如果不存在則爲null
select * from INFO a left join RESULT d on a.id = d.resource_guid
全連接:相當與where條件
select * from INFO a join RESULT d on a.id = d.resource_guid
13. 轉換爲字符串: to_char()
select * from users where to_char('create_time','yyyy-MM-dd')<=sysdate;
14. 時間加天數:時間直接加數字
select * from users where create_time+15 = sysdate;