![]() ![]() This is the table that you wish to add a primary key to. PRAGMA foreign_keys=on table_name The name of the table to modify. ![]() INSERT INTO table_name SELECT * FROM old_table The syntax to add a primary key to a table in SQLite is: PRAGMA foreign_keys=off ĪLTER TABLE table_name RENAME TO old_table ![]() Instead, you must create a new table with the primary key and copy the data into this new table. If your table already exists and you wish to add a primary key later, you can not use the ALTER TABLE statement to create a primary key. So each combination of last_name and first_name must be unique in the customers table. This example creates a primary key on the customers table called customers_pk that is made up of a combination of the last_name and first_name columns. If you create a primary key that is made up of 2 or more columns, you are limited to using only the first syntax where the primary key is defined at the end of the CREATE TABLE statement.ĬONSTRAINT customers_pk PRIMARY KEY (last_name, first_name) We could have used the alternate syntax and created this same primary key as follows: CREATE TABLE employeesīoth of these syntaxes are valid when creating a primary key with only one field. It consists of only one column - the employee_id column. In this example, we've created a primary key on the employees table called employees_pk. We will start with a very simple one where our primary key consists of just one column.ĬONSTRAINT employees_pk PRIMARY KEY (employee_id) Let's look at an example of how to create a primary key using the CREATE TABLE statement in SQLite. pk_col_n The columns that make up the primary key. constraint_name The name of the primary key. column1, column2 The columns that you wish to create in the table. ) table_name The name of the table that you wish to create. pk_col_n)Ĭolumn1 datatype CONSTRAINT constraint_name PRIMARY KEY, The syntax to create a primary key using the CREATE TABLE statement in SQLite is: CREATE TABLE table_nameĬONSTRAINT constraint_name PRIMARY KEY (pk_col1, pk_col2. Create Primary Key (CREATE TABLE statement)Ī primary key can be created when you execute a CREATE TABLE statement in SQLite. ![]()
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