---1.查询索引属于哪个表
select * from user_indexes where index_name =‘索引名称‘
---2.查询系统中所有的索引
select * from user_objects where object_type=‘INDEX‘
---3.查询表中不连续的ID是多少
select * from (select * from yplx_pur) t where not exists (select 1 from yplx_pur where ID=t.ID-1)
原文：https://www.cnblogs.com/fuji-ling/p/14707625.html