Limit should default to 10K

[jvshahid]

Instead of defaulting the start time to now() - 1h, we should be limiting the number of points that are returned to the user, unless they explicitly set LIMIT 0. In which case the limit won't be set.

[FGRibreau]

+1 Cassandra does the same thing:

By default, a query returns 10,000 rows maximum. Using the LIMIT clause, you can change the default limit of 10,000 rows to a lesser or greater number of rows. The default is 10,000 rows.

[hvt]

A followup on this, when I have a serie with > 10k events, and I issue the following query:

select count(column1) from test

I get back 10000. While:

select count(column1) from test limit 0

Gives indeed back the correct number of events.

I get this has to do with this issue. Although I believe this isn't preferable when using group-like functions, right?

[pauldix]

Hmmm yes, you're probably right. We'll reopen and have the limit go away if you're using an aggregate function.

[jvshahid]

I think for the time being we're going to get rid of the default limit. We are thinking about revisiting this issue later to have a database configuration for the maximum number of points a user can retrieve in a query. I'll close this issue with a commit in a little bit.

[pauldix]

This is actually still in the db at https://github.com/influxdb/influxdb/blob/master/src/datastore/leveldb_datastore.go#L773

[jvshahid]

Fixed in 52fad8d