How can i effect Autoincrement in my table

[sshade25]

I created a table of five columns as follows
crop_id, crop_type, crop_name, cultivation_yrs , local_name.

I want to make the crop_id to be the primary key, and also to be autoincremental as well as serve as a reference to a foreign key in the main database table which is a different table altogerther.

I am able to create the primary key and the foreign key but i am not able to achieve the autoincrement

Please how can i achieve this.

[rski]

You can redefine (drop and create again) the table and define the type for column crop_id as 'serial'.
Or you can create now sequence (CREATE SEQUENCE ,,,) and define default for column crop_id as nextval('seqnec e_name') (ALTER TABLE ..)