Set all empty strings to NULL in all records of all tables in PostgreSQL.

Question

I'd like to update all records with an empty string in all columns of all tables in PostgreSQL. Is there a way to do this with a query? Or at least how to query for all columns that don't have a NOT NULL constraint.

Answer 1

Visit the information_schema like this

select * 
from information_schema.columns
where is_nullable = 'YES';

From that data you can generate yourself update statements for all the tables and columns.