I am using the gocql library which is documented here: https://godoc.org/github.com/relops/cqlc/cqlc#Fetchable and am trying to write an API call in golang that will ask for all of the elements in my database that fulfill a particular field and return the total number of elements returned. I know when I am in the Cassandra interface I can use the call SELECT COUNT(*) from table1 WHERE ...; where table1 is the table name. I have been going through the documentation and all I can find is the limit function that limits the number of entries that are returned.
For example, just say I have a database table of events in Cassandra that take place on different days. I just want to return the number of events that take place on Tuesday, and I want to do this using gocql.
Currently I do something like:
cx := cqlc.NewContext()
iter, err := cx.Select().
From(db.EVENTLOG).
Where(db.EVENTLOG.DAY.Eq(day).
Limit(10000).
Fetch(cass)
data, err = db.BindEventlog(iter)
The BindEventLog function returns an array of the events that happen on 'day' but again, I just want the number of events, not the events themselves. Is there a way to get this without iterating through this array because I am anyways going to throw out the array so it would be really slow to get the database to give me the entire array of data.
I am a beginner at this so if you need more information please ask, I tried to make this as specific as possible. Thanks.
The closest thing I could find that would help you out is Iter.NumRows
If they paginate rows that won't give you what you're looking for. In the event that they do, this is a reasonable feature to request on their Github.