How to add empty string as default value for text field in Hasura

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! and your new tag column with a default empty string is added to the posts table.