oracle 笔记1

 sql%rowcount 含义

•sql%rowcount中的sql是oracle的内部游标,rowcount的意思是之前的dml sql语句影响的多少行数据。

•如果是delete操作rowcount就是delete的数据，如果是insert，就是插入的数量......

Connect by prior start with 的用法

 

•通过start with . . .  connect by . . .子语句实现SQL的层次查询

•    SELECT t3.id

•      INTO o_firstTreeId

•      FROM (SELECT t2.*, LEVEL

•               FROM mdo_mc_menu_tree t2

•              WHERE LEVEL = v_levelcount - 1

•              START WITH t2.id = p_menu_treeid

•             CONNECT BY PRIOR t2.parent_id = t2.id) t3;