--对比2表并更新某表数据
MERGE INTO real_yuyuke20101009 a
USING FLOW_CARMASTER b
ON (a.phone = b.relatephone1 ) --条件可加
WHEN MATCHED THEN
UPDATE SET a.carmaster_seq_no = b.seq_no
update flow_gzowntest_zw set rq=trim(rq) 把字段里的空格内容去掉
update web_SJtongji_Callerid set callerid=replace(callerid,chr(10),'') 去掉回车
update FLOW_16842168_3b set id=replace(id,'x','*') 替换字段里的x
根据某个字符截取前面的内容 substr(a.qq_name,0,instr(a.qq_name,'@',1,1)-1)
1、从表中随机取记录
select * from (select * from staff order by dbms_random.random)
表示从STAFF表中随机取3条记录
2、产生随机数
SELECT DBMS_RANDOM.RANDOM FROM DUAL;
产生一个任意大小的随机数
SELECT ABS(MOD(DBMS_RANDOM.RANDOM,100)) FROM DUAL;
产生一个100以内的随机数
SELECT TRUNC(100+900*dbms_random.value) FROM dual;