#IOS6 SQLITE FOREIGN KEY TUTORIAL CODE#
We can use the following code to create these two tables. In this example we’ll make it the primary key. While parent keys are usually also the primary key for the table, this is not actually a requirement. In other words, we want to make Pets.TypeId the child key (with a foreign key constraint), and Types.TypeId the parent key (with a primary key constraint). Imagine we want two tables with the following data.Īnd we want the TypeId column of the Pets table to reference the TypeId column of the Types table. Now that we’ve enabled foreign key support, let’s go ahead and create a foreign key. Note that this setting is not required for creating foreign keys, but it is required for enforcing foreign keys.
If you open another connection, you’ll need to run the same statement for that connection. This will enable foreign key enforcement for your database connection. To do this, run the following statement: PRAGMA foreign_keys = ON The first thing we should do is to enable foreign key support (if it hasn’t already been done).Īssuming your SQLite library hasn’t been compiled with SQLITE_OMIT_FOREIGN_KEY or SQLITE_OMIT_TRIGGER defined, you will still need to enable foreign key support at runtime.
This article provides an example of creating a foreign key when creating a table in SQLite. When you create a table in SQLite, you can also create a foreign key in order to establish a relationship with another table.
0 kommentar(er)
