What does keyword CONSTRAINT do in this CREATE TABLE statement

Question

I\'m learning how to use sqlite3 with python. The example in the text book I am following is a database where each Country record has a Region, Country, and Population.

Answer 1

If you omit CONSTRAINT Contry_Key from the statement, SQL server will generate a name for your PRIMARY KEY constraint for you (the PRIMARY KEY is a type of constraint).

By specifically putting CONSTRAINT in the query you are essentially specifying a name for your primary key constraint.