You can write reusable scripts with Postgres by taking advantage of named variables. A named variable starts with a `:` in your sql script. Here is an example select :a_number You can then use this statement with `psql` and the `--variable` fl...

Unfortunately PHP's PDO constructor doesn't take a database connection url (in a format that Heroku makes available as a config var) as an argument. It has its own, rather odd syntax. However, it's easy enough to extract url parts with the `parse_url`...