Remove this section and replace it with a description of your MR. Also follow the
checklist below and check off any tasks that are done. If a certain task can not
be done you should explain so in the MR body. You are free to remove any
sections that do not apply to your MR.
When gathering statistics (e.g. the output of `EXPLAIN ANALYZE`) you should make
sure your database has enough data. Having around 10 000 rows in the tables
being queries should provide a reasonable estimate of how a query will behave.
Also make sure that PostgreSQL uses the following settings:
*`random_page_cost`: `1`
*`work_mem`: `16MB`
*`maintenance_work_mem`: at least `64MB`
*`shared_buffers`: at least `256MB`
If you have access to GitLab.com's staging environment you should also run your
measurements there, and include the results in this MR.
Add a description of your merge request here. Merge requests without an adequate
description will not be reviewed until one is added.
## Database Checklist
...
...
@@ -23,34 +8,23 @@ When adding migrations:
-[] Updated `db/schema.rb`
-[] Added a `down` method so the migration can be reverted
-[] Added the output of the migration(s) to the MR body
-[] Added the execution time of the migration(s) to the MR body
-[] Added tests for the migration in `spec/migrations` if necessary (e.g. when
migrating data)
-[] Made sure the migration won't interfere with a running GitLab cluster,
for example by disabling transactions for long running migrations
-[] Added tests for the migration in `spec/migrations` if necessary (e.g. when migrating data)
When adding or modifying queries to improve performance:
-[] Included the raw SQL queries of the relevant queries
-[] Included the output of `EXPLAIN ANALYZE` and execution timings of the
relevant queries
-[] Added tests for the relevant changes
When adding indexes:
-[] Described the need for these indexes in the MR body
-[] Made sure existing indexes can not be reused instead
-[] Included data that shows the performance improvement, preferably in the form of a benchmark
-[] Included the output of `EXPLAIN (ANALYZE, BUFFERS)` of the relevant queries
When adding foreign keys to existing tables:
-[] Included a migration to remove orphaned rows in the source table
-[] Included a migration to remove orphaned rows in the source table before adding the foreign key
-[] Removed any instances of `dependent: ...` that may no longer be necessary
When adding tables:
-[] Ordered columns based on their type sizes in descending order
-[] Added foreign keys if necessary
-[] Added indexes if necessary
-[] Ordered columns based on the[Ordering Table Columns](https://docs.gitlab.com/ee/development/ordering_table_columns.html#ordering-table-columns) guidelines
-[] Added foreign keys to any columns pointing to data in other tables
-[] Added indexes for fields that are used in statements such as WHERE, ORDER BY, GROUP BY, and JOINs
When removing columns, tables, indexes or other structures:
...
...
@@ -64,8 +38,6 @@ When removing columns, tables, indexes or other structures:
-[] API support added
-[] Tests added for this feature/bug
- Review
-[] Has been reviewed by UX
-[] Has been reviewed by Frontend
-[] Has been reviewed by Backend
-[] Has been reviewed by Database
-[] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
