Add Create Table With bigint Id As Primary Key as a Rails TIL

rails/create-table-with-bigint-id-as-primary-key.md

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+# Create Table With bigint ID As Primary Key
+
+When creating a new table with an ActiveRecord migration, we specify all the
+fields _except_ the `id`. The `id`, which is the primary key, is implicit. We
+get it by default.
+
+The type of that `id` defaults to `int` which is a 32-bit signed integer.
+
+We can override the type of `id` in a variety of ways. The one I prefer in most
+cases is to make the `id` of type `bigint`. This is a 64-bit signed integer. It
+offers quite a bit more headroom for the number of unique identifies in our
+table.
+
+This can be specified by including `id: :bigint` as an option to the
+`create_table` method.
+
+```rails
+class CreatePosts < ActiveRecord::Migration[8.0]
+  def change
+    create_table :posts, id: :bigint do |t|
+      t.string :title, null: false
+      t.string :body, null: false
+
+      t.timestamps
+    end
+  end
+end
+```
+
+[source](https://api.rubyonrails.org/v7.1/classes/ActiveRecord/ConnectionAdapters/SchemaStatements.html#method-i-create_table)