[Solved] How I can get last row of each day from big mysql table

How to optimize this SQL query?

In case you have your own slow SQL query, you can optimize it automatically here.

For the query above, the following recommendations will be helpful as part of the SQL tuning process.
You'll find 3 sections below:

  1. Description of the steps you can take to speed up the query.
  2. The optimal indexes for this query, which you can copy and create in your database.
  3. An automatically re-written query you can copy and execute in your database.
The optimization process and recommendations:
  1. Avoid Selecting Unnecessary Columns (query line: 2): Avoid selecting all columns with the '*' wildcard, unless you intend to use them all. Selecting redundant columns may result in unnecessary performance degradation.
  2. Create Optimal Indexes (modified query below): The recommended indexes are an integral part of this optimization effort and should be created before testing the execution duration of the optimized query.
  3. Index Function Calls Using Generated Columns (modified query below): When a function is used directly on an indexed column, the database's optimizer won’t be able to use the index to optimize the search. Creating and indexing a generated column (supported in MySQL 5.7) will allow MySQL to optimize the search.
Optimal indexes for this query:
ALTER TABLE `history_average_crypto_stats` ADD INDEX `history_crypto_idx_asset_id_created_at` (`asset_id`,`created_at`);
ALTER TABLE `history_average_crypto_stats` ADD INDEX `history_crypto_idx_asset_id_date_at` (`asset_id`,`date_created_at`);
The optimized query:
        history_average_crypto_stats.`asset_id` = 1 
        AND history_average_crypto_stats.`created_at` >= DATE_SUB(NOW(), INTERVAL 1 YEAR) 
        history_average_crypto_stats.`created_at` ASC

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