[Solved] Need Optimize TIMESTAMPDIFF query
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Need Optimize TIMESTAMPDIFF query

Hi i have little long time query which takes almost 400ms .

this is my query 

 SELECT id, `from` 
 FROM messages 
 WHERE `to` = ? 
 AND `to_viewed` = '0' 
 AND `to_deleted` = '0'
 AND TIMESTAMPDIFF(SECOND,created,?)< 20 AND TIMESTAMPDIFF(SECOND,created,?)>= 0

How can i optimize this ?

obs i have no idex .

EDIT to show my EXPLAIN

  id  select_type  table    type  possible_keys  key  key_len  ref  rows Extra
   1  SIMPLE       messages ALL  created  NULL  NULL  NULL    10   Using where

How to optimize this SQL query?

The following recommendations will help you in your 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. 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.
  2. 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.
  3. Use Numeric Column Types For Numeric Values (query line: 8): Referencing a numeric value (e.g. 0) as a string in a WHERE clause might result in poor performance. Possible impacts of storing numbers as varchars: more space will be used, you won't be able to perform arithmetic operations, the data won't be self-validated, aggregation functions like SUM won't work, the output may sort incorrectly and more. If the column is numeric, remove the quotes from the constant value, to make sure a numeric comparison is done.
  4. Use Numeric Column Types For Numeric Values (query line: 9): Referencing a numeric value (e.g. 0) as a string in a WHERE clause might result in poor performance. Possible impacts of storing numbers as varchars: more space will be used, you won't be able to perform arithmetic operations, the data won't be self-validated, aggregation functions like SUM won't work, the output may sort incorrectly and more. If the column is numeric, remove the quotes from the constant value, to make sure a numeric comparison is done.
Optimal indexes for this query:
ALTER TABLE `messages` ADD INDEX `messages_idx_to_to_view_to_dele_timesta` (`to`,`to_viewed`,`to_deleted`,`timestampdiff_second_created`);
The optimized query:
SELECT
        messages.id,
        messages.`from` 
    FROM
        messages 
    WHERE
        messages.`to` = ? 
        AND messages.`to_viewed` = '0' 
        AND messages.`to_deleted` = '0' 
        AND messages.timestampdiff_second_created < 20 
        AND messages.timestampdiff_second_created >= 0

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