What does this mean in PostgreSQL
columnName citext NULL
Im working on some SQL change, there is data in the database, but doesn’t show in the front end. Wonderig if this NULL makes the values go into null state?
>Solution :
The part you have shown means nothing and won’t work as it is.
This will likely be part of a table definition. If you need further details which differenes exist between CITEXT and TEXT or VARCHAR, you should have a look in the documentation: documentation
The "NULL" at the end just means that this column will be nullable. You can remove this if it confuses you. The opposite would be columnName citext NOT NULL. The entire create table command can look like this:
CREATE TABLE example
(
columnName CITEXT NULL,
columnName2 CITEXT NOT NULL
);
When you want to insert or update rows of this table, only the first column can be null. The second column requires a not null value. As example, this insert will succeed:
INSERT INTO example VALUES (NULL,'1');
But this one will fail:
INSERT INTO example VALUES ('1',NULL);