PostgreSQL判断表是否存在最快的方法

https://blog.youkuaiyun.com/kmblack1/article/details/78398602

 

速度最快,9.4或更高版本首选这个函数 可以判断临时表 

if( to_regclass('test') is null ) then 你的代码 end if;

 -----------------------------------------------------

方法一： pg_class 不可以判断临时表

if( (select 1 from pg_class where relname='test'::name and relkind='r') is null ) then /*你的代码*/ end if;

----或

select count(*) from pg_class where relname = 'tablename';

方法二：information_schema 可以判断临时表 

if( (select 1 from information_schema.tables

where table_schema = 'public' and table_name = 'test') is null )

then /*你的代码*/ end if;

----或

select count(*) from information_schema.tables

where table_schema='public'

and table_type='BASE TABLE'

and table_name='tablename';

 

方法三：pg_tables catalog

if( (select 1 from pg_tables where schemaname = 'public' and tablename = 'test') is null )

then /*你的代码*/ end if;