摘要: 1. 做一个3*3的加法表SQL> select a||'+'||b||'='||(a+b) from (select rownum a from all_objects where rownum0 and b.n0 and c.n0 and d.n0;6.每个雇员的薪水(SAL)都对应到一个薪水级... 阅读全文
posted @ 2015-06-30 17:28 劃云 阅读(160) 评论(0) 推荐(0) 编辑