1.
ALTER TABLE tabname ADD CONSTRAINT
chk_name CHECK
(substr(Field1,1,3) in ('aaa','bbb','ccc'));2.create table t_logbak as select * from t_log where months_between(sysdate,logDatetime)<6;
drop table t_log;
rename table t_logbak to t_log;
3.java pool,rebo buffer,database buffer,large pool,share pool4.local extent management,dictionary extent management5.题目是不是打错了几个字?
ALTER TABLE tabname ADD CONSTRAINT
chk_name CHECK
(substr(Field1,1,3) in ('aaa','bbb','ccc'));2.create table t_logbak as select * from t_log where months_between(sysdate,logDatetime)<6;
drop table t_log;
rename table t_logbak to t_log;
3.java pool,rebo buffer,database buffer,large pool,share pool4.local extent management,dictionary extent management5.题目是不是打错了几个字?
解决方案 »
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