Add Create Table Adds A Data Type as a postgres til

postgres/create-table-adds-a-data-type.md

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+# Create Table Adds A Data Type
+
+Each time you create a table in PostgreSQL, a new data type represented by
+that table is created and added to the `pg_type` table. According to the
+Postgres docs:
+
+> CREATE TABLE also automatically creates a data type that represents the
+> composite type corresponding to one row of the table. Therefore, tables
+> cannot have the same name as any existing data type in the same schema.
+
+For instance, if you create a `users` table like so:
+
+```sql
+create table users (
+  id serial primary key,
+  first_name varchar not null,
+  last_name varchar not null
+);
+```
+
+then the `pg_type` will now contain an entry with a `typname` of `users`.
+
+```sql
+select * from pg_type where typname = 'users';
+-[ RECORD 1 ]--+------------
+typname        | users
+typnamespace   | 2200
+typowner       | 16384
+...
+```
+
+h/t Bruce Momjian