Oracle Connect By用法
oracle中的select語句可以用START WITH...CONNECT BY PRIOR子句實現遞歸查詢,connect by 是結構化查詢中用到的,其基本語法是:
select ... from <TableName>
where <Conditional-1>
start with <Conditional-2>
connect by <Conditional-3>
;
<Conditional-1>:過濾條件,用于對返回的所有記錄進行過濾。
<Conditional-2>:查詢結果重起始根結點的限定條件。
<Conditional-3>:連接條件
select * from t_department where levels=2 start with id = 'D-06-04' connect by prior superior=id;
oracle中的select語句可以用START WITH...CONNECT BY PRIOR子句實現遞歸查詢,connect by 是結構化查詢中用到的,其基本語法是:
select ... from <TableName>
where <Conditional-1>
start with <Conditional-2>
connect by <Conditional-3>
;
<Conditional-1>:過濾條件,用于對返回的所有記錄進行過濾。
<Conditional-2>:查詢結果重起始根結點的限定條件。
<Conditional-3>:連接條件
select * from t_department where levels=2 start with id = 'D-06-04' connect by prior superior=id;