摘要：select * from t_s_da_sec_var r start with c_da_code='FZ_FZ' connect by nocycle prior r.c_da_code_p=r.c_da_code ;select * from t_s_da_sec_var r start w 阅读全文

摘要：--关于null在oracle数据库中是否参与计算,进行验证,with td as (select null id,1 name from dual ),td1 as ( select null id,2 name from dual ) select * from td, td1 where nv 阅读全文