[DRILL-3165] Sorting a Mongo table should leverage Mongo Indexes

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.0.0
• Fix Version/s: Future
• Component/s: Storage - MongoDB
• Assignee: Unassigned
• Reporter: Leandro DG
• Created: 21/May/15 16:14
• Updated: 17/Nov/16 04:37

Description

When doing a query using Mongo, sorting takes place entirely in Drill.

Getting the first 1000 rows from a 1000000 rows table, sorted by a field which has an index takes a long time (about 45 seconds in our test environment).

Sample drill query:
Select c.name from mongo.foo.json_customers c order by c.name limit 1000

Doing the same in mongo client takes less than a second.

Sample mongo query: db.json_customers.find().sort(

{"name":1}

).limit(1000)

Sorting by a field should leverage the existing mongo indexes if they exist.