Oracle 常用statement Knowledge

select TO_CHAR(SYSDATE,'YYYY-MM-DD HH24:MI:SS') from pt_access  ---需要有一个载体
结果:2008-12-16 14:46:52
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TO_NUMBER(STR)：将字符串转换成数字；若转换不成功，则抛错：ORA-01722: invalid number；
select to_number(seq_no) from pt_importbill
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sername,factory_no,roleno,Upper(userid) from pt_user
SHAPENG
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