AggregateFunctions

Clear offers helpers to call aggregate functions over your models.

Count

Count can be used over the query system:

User.query.count

By default, count return a Int64, but you can select the type of output you are looking for:

User.query.count(UInt32)

Count is working too with pagination:

User.query.offset(15).limit(5).count # Will return SELECT COUNT(*) FROM (SELECT 1 FROM users OFFSET 15 LIMIT 5)

MIN, MAX, AVG

Min, Max and Average are callable through the query system:

  last_id = User.query.max(:id, UInt64)

Customizable Aggregates

It's possible to call custom aggregate function like Median using agg:

weighted_avg = User.query.agg( "SUM(performance_weight * performance_score) / SUM(performance_weight)", Float64 )