486201 - Evaluate possible optimization for table 'cal_recurrence' using an index

Status: RESOLVED INVALID

(Calendar :: Provider: Local Storage, enhancement)

Description

[Daniel Boelzle [:dbo]]

Using a debug build I get the following warning:

WARNING: 1 sort operation has occurred for the SQL statement 'SELECT * FROM cal_recurrence WHERE item_id = :item_id AND cal_id = 0 ORDER BY recur_index'.  This may indicate an opportunity to improve performance through the careful use of indexes.: file /Users/dbo/moz_cc/src/mozilla/storage/src/mozStoragePrivateHelpers.cpp, line 105

Comment 1

[Martin Schröder [:mschroeder]]

When introducing an index for this query we have to compare using an index for item_id/cal_id and recur_index (according to http://www.sqlite.org/optoverview.html). After bug 529326 has landed, we use an index for item_id/cal_id.

Comment 2

[Martin Schröder [:mschroeder]]

Indices have been added in bug 529326, and the missing index on "recur_index" is no longer needed as bug 785733 removed "ORDER BY recur_index" from the query.

Maybe we should file a bug removing column "recur_index" from table "cal_recurrence" as it seems to be no longer used.

Comment 3

[Martin Schröder [:mschroeder]]

(In reply to Martin Schröder [:mschroeder] from comment #2)
> Maybe we should file a bug removing column "recur_index" from table
> "cal_recurrence" as it seems to be no longer used.

Not needed as bug 785733 took care of that in its migration/upgrade step.