oracle案例

select * from G_JDCL where rownum=1;
delete from quchong_1 where rownum=1;
truncate table quchong;

//查看表结构
select COLUMN_NAME,DATA_TYPE,DATA_LENGTH from user_tab_cols where table_name='G_JDCL';

select table_name,constraint_name,constraint_type from dba_constraints
where table_name='G_JDCL';

//删除重复,创建临时表
CREATE TABLE quchong_1 AS (select distinct * from quchong);
//查询数据表内存
SELECT SUM（BYTES）/1024/1024 FROM DBA_EXTENTS WHERE SEGMENT_NAME = 'QUCHONG';

DELETE from quchong WHERE (HPHM) IN ( SELECT HPHM FROM quchong GROUP BY HPHM HAVING COUNT(HPHM) > 1) AND ROWID NOT IN (SELECT MIN(ROWID) FROM quchong GROUP BY HPHM HAVING COUNT(*) > 1);

//从quchong_1的表中取第一条数据赋值给str之后插入目标表
declare
j number;
i number;
str VARCHAR2(50);
begin 
i:=1;
j:=1;
for i in 1..3040000 loop
 select HPHM into str from quchong_1 where rownum = 1; 
 delete from quchong_1 where rownum=1;
insert into g_jdcl(XH, HPZL, HPHM, CLXH, CLLX, CSYS, CLPP1) values(to_char(j),'01',str,'1','K33','A','奥迪');
j:=j+1;
IF Mod(j,5000)=0 
THEN 
   COMMIT; 
   dbms_output.put_line('over!');
END IF; 
end loop;

end;