create table table1(id varchar2(100) primary key,name varchar2(1000),address varchar2(1000));

-- 执行两次，会报  [Err] ORA-00001: unique constraint (PBOC.SYS_C0014610) violated

insert into table1(id,name,address)values('','影子','河北') ;

-- 查看constraint

SELECT UC.OWNER,

       UC.CONSTRAINT_NAME,

       UC.CONSTRAINT_TYPE,

       UC.TABLE_NAME,

       UCC.COLUMN_NAME,

       UC.SEARCH_CONDITION,

       UC.R_CONSTRAINT_NAME

FROM USER_CONSTRAINTS UC

  INNER JOIN USER_CONS_COLUMNS UCC

    ON (UC.CONSTRAINT_NAME = UCC.CONSTRAINT_NAME) and UC.TABLE_NAME='TABLE1';

-- merge有则更新，无责插入

merge into table1 t1

using (select '' id,'影子2' name,'辽宁' address from dual) t2

on (t1.id = t2.id)

when matched then

     update set t1.name = t2.name, t1.address = t2.address

when not matched then

     insert values (t2.id, t2.name,t2.address);  

select * from table1;

drop table table1;

create table table1(id varchar(100) primary key,name varchar(1000),address varchar(1000));

-- 执行两次，会报  [Err] 1062 - Duplicate entry '01001' for key 'PRIMARY'

insert into table1(id,name,address)values('','yingzi','hebei') ;

-- 无责插入（返回：受影响的行: 1），有则更改（返回：受影响的行: 2）

INSERT INTO  table1(id,name,address) VALUES ('','yingzi2','hunan')  ON DUPLICATE KEY UPDATE name='yingzi2',address='hunan';

select * from table1;

drop table table1;