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add index on invite_email to members

yun guo requested to merge issue-62685 into master

What does this MR do?

It creates an index on invite_email on members table to speed up query

SELECT "members".\* FROM "members"   
WHERE "members"."invite_email"   
IN (?, ?) AND ("members"."invite_token"   
IS NOT NULL)

it improves the execution time from 4,226.324 ms to 0.053 ms

Before the migration execution plan: https://explain.depesz.com/s/oFFy

after the migration execution plan: https://explain.depesz.com/s/HhvS

Database checklist

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 tests for the migration in spec/migrations if necessary (e.g. when migrating data)

When adding or modifying queries to improve performance:

  • 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 before adding the foreign key
  • Removed any instances of dependent: ... that may no longer be necessary

When adding tables:

  • Ordered columns based on the 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:

  • Removed these in a post-deployment migration
  • Made sure the application no longer uses (or ignores) these structures

General checklist

Edited by yun guo

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