string - 如何比较字符串和整数 Postgres

Question

如何在 Postgres 中将空字符串与整数进行比较？

例如：Select * From xyz where anynumber = ''

Answer 1

A numeric column can't be "blank", but it can be null. I think that's what you want:

Given that anynumber is nullable, ie

create table xyz (
    ...
    anynumber int,  -- ie not "NOT NULL"
    ...
)

You can test for null:

select * From xyz where anynumber is null