What difference between NULL and NULL::character varying in PostgreSQL

Question

Is there a difference between default values of column in PostgreSQL? Whether this is important?

state character varying(255) DEFAULT NULL

and

state character varying(255) DEFAULT NULL::character varying

Erwin Brandstetter · Accepted Answer · 2022-03-08 03:40:52Z

9

There is no effective difference in the presented example in a standard installation.

Without explicit cast, NULL of data type unknown will be coerced to varchar in an assignment cast automatically. See:

Generate series of dates - using date type as input

In other situations, where the type cannot be derived from context, you may need to cast explicitly - to tell Postgres the intended type of the value. This is rarely the case, though.

edited Mar 8, 2022 at 3:40

answered Jul 23, 2014 at 13:54

Erwin Brandstetter

669k160 gold badges1.2k silver badges1.3k bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

What difference between NULL and NULL::character varying in PostgreSQL

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related