PL/Swift Documentation

PL/Swift allows you to write custom SQL functions and types for the PostgreSQL database server in the Swift programming language.

What is an PostgreSQL extension?

The PostgreSQL database server is quite modular and can be extended with custom SQL functions and custom SQL types.

Such extensions can be written in PSQL itself, in scripting languages such as Python or TCL, and in plain C.

Now PL/Swift allows you to write extensions using Swift.

Assume you have a Swift function which turns an integer into a base36 encoded String, to replicate the trick used by URL shorteners (""):

func base36_encode(_ v: Int) -> String {
  return String(v, radix: 36)

and now you would like to use that in a SQL query, like so:

helge=# SELECT base36_encode(31337);
(1 row)

This is what PL/Swift does. It helps you expose your Swift functions to PostgreSQL.