发生报错环境
表数据量大，为了减轻查询压力，使用了分区表。手动删除分区表后出现了表结果报错，主表无法正常打开。
错误内容：
ERROR: cache lookup failed for relation 63122
操作前先备份表和数据。
排查过程
查看该表内容
database=# \d table_name
ERROR: cache lookup failed for relation 63122
查询资料，表信息都在pg_class 与 pg_depend表中
database=# select relname, oid from pg_class where relname='table_name';
relname | oid
--------------------+-------
tableb_name | 78105
删除相关的oid信息
database=# delete from pg_class where oid=63122;
DELETE 1
database=# delete from pg_depend where objid=63122;
DELETE 1
将表相关联的索引，序列和约束都删掉
select oid, relname from pg_class where relname like '%table_name%';
将查询出来该表相关的 ix_table_name_id, table_name_id_seq, table_name_pkey等删除掉
delete from pg_class where oid=9578;
delete from pg_depend where objid=9578;
然后尝试重建表，又报了一个错误
ERROR： type 'table_name' already exists HINT: A relation has an associated type of the same name, so you must use ...
此处应该发现若是表存在的话应该报的错误是
ERROR: relation "table_name" already exists
既然type 已存在, 就将该type删除
下面是在 DROP TYPE的时候还报 cache lookup failed for relation 63122的错误，感觉没有删除干净有查询到pg_depend表的refobjid中存在该id的引用
database=# delete from pg_depend where refobjid=78105;
DELETE 4
最后删除该表TYPE
database=# DROP TYPE table_name;
DROP TYPE
