activerecord-explain-analyze
Extends ActiveRecord#explain with support for EXPLAIN ANALYZE and output formats of JSON, XML, and YAML.
It currently supports ActiveRecord 4 and 5, and PostgreSQL only.
Examples:
Wallet.where(base_currency: "USD").explain(analyze: true)
Results in:
EXPLAIN for: SELECT "wallets".* FROM "wallets" WHERE "wallets"."deleted_at" IS NULL AND "wallets"."base_currency" = $1
Bitmap Heap Scan on public.wallets (cost=4.16..9.50 rows=1 width=164) (actual time=0.008..0.012 rows=30 loops=1)
Output: id, canonical_id, client_id, wallet_type, base_currency, created_at, updated_at, deleted_at
Recheck Cond: (wallets.deleted_at IS NULL)
Filter: ((wallets.base_currency)::text = 'USD'::text)
Heap Blocks: exact=1
Buffers: shared hit=2
-> Bitmap Index Scan on index_wallets_on_deleted_at (cost=0.00..4.16 rows=2 width=0) (actual time=0.003..0.003 rows=32 loops=1)
Index Cond: (wallets.deleted_at IS NULL)
Buffers: shared hit=1
Planning time: 0.041 ms
Execution time: 0.026 ms
Wallet.where(base_currency: "USD").explain(analyze: true, format: :json)
Results in:
[
{
"Plan": {
"Node Type": "Bitmap Heap Scan",
"Parallel Aware": false,
"Relation Name": "wallets",
"Schema": "public",
"Alias": "wallets",
"Startup Cost": 4.16,
"Total Cost": 9.50,
"Plan Rows": 1,
"Plan Width": 164,
"Actual Startup Time": 0.008,
"Actual Total Time": 0.013,
"Actual Rows": 30,
...
You can then paste this JSON output into PEV or similar tools to get a visualization of the EXPLAIN query output:
Installation
Add this line to your application's Gemfile and run bundle
to install:
gem 'activerecord-explain-analyze'
Development
After checking out the repo, run bin/setup
to install dependencies. Then, run rake spec
to run the tests. You can also run bin/console
for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install
. To release a new version, update the version number in version.rb
, and then run bundle exec rake release
, which will create a git tag for the version, push git commits and tags, and push the .gem
file to rubygems.org.