Let's say we have a table posts and we want to add a new column tag which should be an empty string by default.
We can not add our tag text field with a default empty string using the Hasura console's "Add a new column". Instead we must add the column manually to the PostgreSQL database.
Click on SQL in the left menu in the Hasura console to insert the following SQL statement:
ALTER TABLE "posts" ADD COLUMN "tag" text NOT NULL DEFAULT '';
Click Run. Your new tag column with a default empty string is added to the posts table!