摘要:
由一個sql引發的思考: select * from z_test1 where id <> '' 先說結果:在oracle中啥也查不出來原因是:oracle中對空串都會視為NULL處理,如上sql等同于 select * from z_test1 where id <> NULL 但是對NULL執 閱讀全文
摘要:
1、connect by 是結構化查詢中用到的,其基本語法是:select … from tablename start with 條件1connect by 條件2where 條件3;例:select * from tablestart with org_id = ‘HBHqfWGWPy’conn 閱讀全文