Queries on empty array causes TinyTds to throw

[joshleblanc]

Issue

Given the following code MyModel.where(id: []), TinyTds will raise the following error:

ActiveRecord::StatementInvalid (TinyTds::Error: The isnull function requires 2 argument(s).)

Expected behavior

The adapter should return an empty collection

Actual behavior

It throws

How to reproduce

1. Query a table with an empty array

Details

• Rails version: 6.0.3.2
• SQL Server adapter version: 6.0.0
• TinyTDS version: 2.1.3.pre

[joshleblanc]

This also happens just by assigning the attribute to an empty array, or nil.

Machine.first.machine_group_ids = []
ActiveRecord::StatementInvalid (TinyTds::Error: The isnull function requires 2 argument(s).)