Parameters

Parameter is a placeholder for a value provided after the compilation of the query.

It uses the following syntax: $id, where id is an arbitrary alpha numeric string.

Most database engines only support numeric positional parameter ids (i.e $3).

PRQL

1. from employees
2. filter id == $1

SQL

1. SELECT
2. *
3. FROM
4. employees
5. WHERE
6. id = $1