PostgreSQL教程--数据库查询表是否存在数据库中，表字段信息及主外键

1、查询表是否存在数据库

select * from information_schema.tables where table_schema='public' and table_type='BASE TABLE' and table_name='表名称';

2、查询表字段信息

select * from information_schema.columns where table_schema='public' and table_name='表名称';

3、查询主键外键

select kcu.table_schema,
       kcu.table_name,
       tco.constraint_name,
       kcu.ordinal_position as position,
       kcu.column_name as key_column,
             tco.constraint_type
from information_schema.table_constraints tco
join information_schema.key_column_usage kcu 
     on kcu.constraint_name = tco.constraint_name
     and kcu.constraint_schema = tco.constraint_schema
     and kcu.constraint_name = tco.constraint_name
where kcu.table_schema='public' and 
         kcu.table_name='表名称';