AwesomeExplain
AwesomeExplain provides the same APM's level of query analysis under your development and test Rails environments.
Main Features
- A set of utilities for analyzing MongoDB and SQL queries from Rails console.
- Tracking queries under your database of choice (SQLite3 or PostgreSQL) which can be viewed under Athena's dashboard.
Installation
Add the following line to your application's Gemfile:
gem 'awesome_explain', require: true
Console Utility Methods
-
ae: Prints a query's execution plan using a user friendly terminal table
- Currently supports the following classes:
Mongo::Collection::View::Aggregation
Mongoid::Criteria
ActiveRecord::Relation
- Currently supports the following classes:
- analyze: Prints a summary of all MongoDB queries passed to the Ruby block
- analyze_ar: Prints a summary of all ActiveRecord queries passed to the Ruby block
Detailed usage examples can be found below.
MongoDB
Usage
ae Article.where(author_id: '5b9ec484d5cc2e697189d7c9')
+--------------------+-----------------------------+
| Winning Plan | FETCH (7 / 7) -> IXSCAN (7) |
+--------------------+-----------------------------+
| Used Indexes | author_id_1 (forward) |
+--------------------+-----------------------------+
| Rejected Plans | 0 |
+--------------------+-----------------------------+
| Documents Returned | 7 |
+--------------------+-----------------------------+
| Documents Examined | 7 |
+--------------------+-----------------------------+
| Keys Examined | 7 |
+--------------------+-----------------------------+
| Execution time(ms) | 0 |
+--------------------+-----------------------------+
| Execution time(s) | 0.0 |
+--------------------+-----------------------------+
ae Article.or([{author_id: '5b9ec484d5cc2e697189d7c9', state: 'published'}, {created_at: 3.days.ago}])
+--------------------+-------------------------------------------------------------------------------------------------------------------------------------------+
| Winning Plan | SORT (20) -> SORT_KEY_GENERATOR (20) -> FETCH (24 / 20) -> OR (24) -> [ FETCH (24 / 24) -> IXSCAN (24) , FETCH (0 / 0) -> IXSCAN (0) ] |
+--------------------+-------------------------------------------------------------------------------------------------------------------------------------------+
| Used Indexes | state_1 (forward), author_id_1 (forward) |
+--------------------+-------------------------------------------------------------------------------------------------------------------------------------------+
| Rejected Plans | 18 |
+--------------------+-------------------------------------------------------------------------------------------------------------------------------------------+
| Documents Returned | 20 |
+--------------------+-------------------------------------------------------------------------------------------------------------------------------------------+
| Documents Examined | 48 |
+--------------------+-------------------------------------------------------------------------------------------------------------------------------------------+
| Keys Examined | 24 |
+--------------------+-------------------------------------------------------------------------------------------------------------------------------------------+
| Execution time(ms) | 37 |
+--------------------+-------------------------------------------------------------------------------------------------------------------------------------------+
| Execution time(s) | 0.037 |
+--------------------+-------------------------------------------------------------------------------------------------------------------------------------------+
ae Product.where(_id: 22)
+--------------------+----------------+
| Winning Plan | IDHACK (1 / 1) |
+--------------------+----------------+
| Used Indexes | |
+--------------------+----------------+
| Rejected Plans | 0 |
+--------------------+----------------+
| Documents Returned | 1 |
+--------------------+----------------+
| Documents Examined | 1 |
+--------------------+----------------+
| Keys Examined | 1 |
+--------------------+----------------+
| Execution time(ms) | 90 |
+--------------------+----------------+
| Execution time(s) | 0.09 |
+--------------------+----------------+
Winning Plan Examples
FETCH (7 / 7) -> IXSCAN (7)
Below is a breakdown of the above winning plan:
- First stage is a
FETCH
stage. 7 documents were examined, and 7 were returned. - Second stage was an
IXSCAN
stage were 7 documents were returned.
For information about MongoDB's explain output, please refer to the official MongoDB Explain documentation: https://docs.mongodb.com/manual/reference/explain-results/
PostgreSQL
ae Usage
Query using PK index
ae Film.where(film_id: 1)
+--------------------+-------+
| General Stats |
+--------------------+-------+
| Table | Count |
+--------------------+-------+
| Total Rows Planned | 1 |
| Total Rows | 1 |
| Total Loops | 1 |
| Seq Scans | 0 |
| Indexes Used | 1 |
+--------------------+-------+
| Table Stats |
+--------------------+-------+
| Table | Count |
+--------------------+-------+
| film | 1 |
+--------------------+-------+
| Node Type Stats |
+--------------------+-------+
| Node Type | Count |
+--------------------+-------+
| Index Scan | 1 |
+--------------------+-------+
| Index Stats |
+--------------------+-------+
| Index Name | Count |
+--------------------+-------+
| film_pkey | 1 |
+--------------------+-------+
Query not using any index
ae Film.where(description: 'Alien Center')
+--------------------+-------+
| General Stats |
+--------------------+-------+
| Table | Count |
+--------------------+-------+
| Total Rows Planned | 1 |
| Total Rows | 0 |
| Total Loops | 1 |
| Seq Scans | 1 |
| Indexes Used | 0 |
+--------------------+-------+
| Table Stats |
+--------------------+-------+
| Table | Count |
+--------------------+-------+
| film | 1 |
+--------------------+-------+
| Node Type Stats |
+--------------------+-------+
| Node Type | Count |
+--------------------+-------+
| Seq Scan | 1 |
+--------------------+-------+
analyze_ar Usage
analyze_ar { Film.where(film_id: 1).to_a; Actor.where(last_name: 'Cage').to_a };0
+--------------------+----------------+
| Time (sec) | 0.0 |
+--------------------+----------------+
| Total Rows Planned | 3 |
+--------------------+----------------+
| Total Rows | 3 |
+--------------------+----------------+
| Total Loops | 2 |
+--------------------+----------------+
| Seq Scans | 1 |
+--------------------+----------------+
| Tables | film (1) |
| | actor (1) |
+--------------------+----------------+
| Node Types | Index Scan (1) |
| | Seq Scan (1) |
+--------------------+----------------+
| Indexes | film_pkey (1) |
+--------------------+----------------+
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/sandboxws/awesome_explain. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.
License
The gem is available as open source under the terms of the MIT License.
Code of Conduct
Everyone interacting in the AwesomeExplain project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.