Add Fetch Specific Number Of Results as a Postgres TIL

postgres/fetch-specific-number-of-results.md

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+# Fetch Specific Number Of Results
+
+If you pull up just about any intro to PostgreSQL (or even SQL), one of the
+first things they are going to teach you is the `limit` clause. This is taught
+as _the_ way for limiting the result set to a specific number of rows.
+
+```sql
+> select title from books limit 4;
++-----------------------+
+| title                 |
+|-----------------------|
+| The Secret History    |
+| A Gentleman in Moscow |
+| Exhalation: Stores    |
+| Annihilation          |
++-----------------------+
+SELECT 4
+```
+
+You might be as surprised as I was to learn that `limit` is not part of the SQL
+standard. It is extremely common for this use case, but the SQL standard
+defines `fetch first N rows only` as the way to fetch a specific number of
+rows. As we can see, [it works identically to `limit
+N`](https://www.postgresql.org/docs/current/sql-select.html#SQL-LIMIT).
+
+```sql
+> select title from books fetch first 4 rows only;
++-----------------------+
+| title                 |
+|-----------------------|
+| The Secret History    |
+| A Gentleman in Moscow |
+| Exhalation: Stores    |
+| Annihilation          |
++-----------------------+
+SELECT 4
+```
+
+The `rows` and `row` keywords are interchangeable which makes statements more
+readable if, for instance, you're doing `... fetch first 1 row only`.
+
+[source](https://www.cybertec-postgresql.com/en/postgresql-limit-vs-fetch-first-rows-with-ties/)