What happens if a delete query times out SQL Server for php? Technology

I am using the mssql extension to php (on linux) to send queries to SQL Server. 

The Setup.

I have a table that builds up disposable data rather quickly. It took me longer than expected to build a cron to clean out this data every hour so it has been accumulating over months to be well over 1G of data not sure how many rows but probably over 1 million.

The Problem

So I ran a delete query for anything older than 1 day. 

DELETE FROM CacheForms WHERE TimeStamp &lt; 1503454349


However after 60sec the query times out and the script fails. (update the same happens at 10min.)

The Question

When this delete query times out (a php concept) what happens to the database? Does the database restore the deleted data from transaction log? or is the data truly deleted? Or does the query keep running in sql server?
When a timeout occurs, the client API sends an attention signal to SQL Server to cancel the executing query. Upon receipt, SQL Server cancels the query and rolls back the transaction. Data modification statements are run in autocommit mode by default so each statement is all-or-none.