內容來自 oracle 11g 實用教程 鄭阿奇等編
在 oracle 11g中有merge語句,用於根據與原表連接的結果,對目標表執行插入,更新,或者刪除操作。例如,根據在一個表中找到的差異在另一個表中插入,更新或者刪除行,這種方法可以對兩個表進行信息同步。語法格式如下
merge into <目標表名>
using <原表名>on <條件表達式>
when matched then {update set ...|delete}
when not matched then insert(...) values()
merge into a
using xsb on (a.xh=xsb.學號)
when matched then update set a.xm = xsb.姓名,a.xb=xsb.性別,a.cssj = xsb.出生時間,a.zy=xsb.專業,a.zxf=xsb.總學分,a.bz=xsb.備注
when not matched then insert values(xsb.學號,xsb.姓名,xsb.性別,xsb.出生時間,xsb.專業,xsb.總學分,xsb.備注)
數據庫
create table a ( XH char(6) not null primary key, xM char(8) not null, XB char(2) not null, CSSJ date not null, ZY char(24) null, ZXF number(2) null, BZ varchar(200) null );
-------------------------------------------------------- -- 文件已創建 - 星期日-七月-24-2016 -------------------------------------------------------- -------------------------------------------------------- -- DDL for Table XSB -------------------------------------------------------- CREATE TABLE "SCOTT"."XSB" ( "學號" CHAR(6 BYTE), "姓名" CHAR(8 BYTE), "性別" CHAR(2 BYTE) DEFAULT '男', "出生時間" DATE, "專業" CHAR(12 BYTE), "總學分" NUMBER(2,0), "備注" VARCHAR2(200 BYTE) ) SEGMENT CREATION IMMEDIATE PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "USERS" ; REM INSERTING into SCOTT.XSB SET DEFINE OFF; Insert into SCOTT.XSB (學號,姓名,性別,出生時間,專業,總學分,備注) values ('151114','周何駿 ','男',to_date('25-9月 -98','DD-MON-RR'),'計算機 ',90,null); Insert into SCOTT.XSB (學號,姓名,性別,出生時間,專業,總學分,備注) values ('151101','王林 ','男',to_date('02-10月-97','DD-MON-RR'),'計算機 ',50,null); Insert into SCOTT.XSB (學號,姓名,性別,出生時間,專業,總學分,備注) values ('151103','王燕 ','女',to_date('10-6月 -96','DD-MON-RR'),'計算機 ',50,null); Insert into SCOTT.XSB (學號,姓名,性別,出生時間,專業,總學分,備注) values ('151202','王林 ','男',to_date('29-1月 -96','DD-MON-RR'),'通信工程 ',40,'有一門課不及格,待補考'); Insert into SCOTT.XSB (學號,姓名,性別,出生時間,專業,總學分,備注) values ('151108','林一帆 ','男',to_date('08-5月 -96','DD-MON-RR'),'計算機 ',52,'已提前修完一門課'); Insert into SCOTT.XSB (學號,姓名,性別,出生時間,專業,總學分,備注) values ('151204','馬琳琳 ','女',to_date('02-10月-96','DD-MON-RR'),'通信工程 ',42,null); -------------------------------------------------------- -- DDL for Index SYS_C0011202 -------------------------------------------------------- CREATE UNIQUE INDEX "SCOTT"."SYS_C0011202" ON "SCOTT"."XSB" ("學號") PCTFREE 10 INITRANS 2 MAXTRANS 255 COMPUTE STATISTICS STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "USERS" ; -------------------------------------------------------- -- Constraints for Table XSB -------------------------------------------------------- ALTER TABLE "SCOTT"."XSB" MODIFY ("學號" NOT NULL ENABLE); ALTER TABLE "SCOTT"."XSB" MODIFY ("姓名" NOT NULL ENABLE); ALTER TABLE "SCOTT"."XSB" MODIFY ("性別" NOT NULL ENABLE); ALTER TABLE "SCOTT"."XSB" MODIFY ("出生時間" NOT NULL ENABLE); ALTER TABLE "SCOTT"."XSB" ADD PRIMARY KEY ("學號") USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 COMPUTE STATISTICS STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "USERS" ENABLE;