【DWS】函数依赖查询

【摘要】删除视图前需要确认是否存在函数依赖和分别依赖于哪些表，可通过以下步骤进行查询

1.select oid from pg_proc where proname ='json_extract_path_text';

2.select classid,objid from pg_depend where refobjid in(第一步查出的refobjid);

3.select relname from pg_class where oid='classid';--根据relname查对应的信息

4.select ev_class from '上一步查出的relname' where oid in (第二步的objid);

5.select relname from pg_class where oid in (第四步ev_class);