Add Get The Size of A Database as a postgres til

README.md

@@ -151,6 +151,7 @@ _319 TILs and counting..._
 - [Fizzbuzz With Common Table Expressions](postgres/fizzbuzz-with-common-table-expressions.md)
 - [Generate A UUID](postgres/generate-a-uuid.md)
 - [Generate Series Of Numbers](postgres/generate-series-of-numbers.md)
+- [Get The Size Of A Database](postgres/get-the-size-of-a-database.md)
 - [Getting A Slice Of An Array](postgres/getting-a-slice-of-an-array.md)
 - [Insert Just The Defaults](postgres/insert-just-the-defaults.md)
 - [Integers In Postgres](postgres/integers-in-postgres.md)

postgres/get-the-size-of-a-database.md

@@ -0,0 +1,16 @@
+# Get The Size Of A Database
+
+If you have connect access to a database, you can use the
+`pg_database_size()` function to get the size of a database in bytes.
+
+```sql
+> select pg_database_size('hr_hotels');
+ pg_database_size
+------------------
+          8249516
+```
+
+Just give it the name of the database and it will tell you how much disk
+space that database is taking up.
+
+Checkout [the Postgres docs](http://www.postgresql.org/docs/current/static/functions-admin.html) for more details.