Sqlite browser foreign key1/30/2024 ![]() The following code adds a foreign key to our table by creating a new table with a foreign key constraint, transferring the data to that table, dropping the original table, then renaming the new table to the name of the original table. (That’s blank because there are no foreign key constraints on this table.) We can verify that there are no foreign keys by running the following command: PRAGMA foreign_key_list(Pets) ![]() Notice that I didn’t create a foreign key. Two tables, because one ( Types) will have the primary key and the other ( Pets) will have the foreign key. CREATE TABLE Types(Īctually, here I created two tables and populated them with data. Original Table Without Foreign Keyįirst, let’s create a table without a foreign key and populate it with data. To make it somewhat realistic, we’ll make sure the table already contains data. The SQLite documentation recommends a 12 step process for making schema changes to a table.įor the purposes of this article, we’ll just deal with adding a foreign key. There’s more than one way to do this, but there is a recommended way. Therefore, the only way you can “add” a foreign key to an existing table in SQLite is to create a new table with a foreign key, then transfer the data to the new table. In other words, you can’t use ALTER TABLE to add a foreign key to an existing table like you can in other database management systems. ![]() The only things you can do with ALTER TABLE in SQLite is rename a table, rename a column within a table, or add a new column to an existing table. SQLite supports a very limited subset of the ALTER TABLE statement.
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