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:
- Description of the steps you can take to speed up the query.
- The optimal indexes for this query, which you can copy and create in your database.
- An automatically re-written query you can copy and execute in your database.
The optimization process and recommendations:
- 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.
- Use Equality Operator Over LIKE (modified query below): Equality operators (such as '\u003d') are usually better optimized and more readable. Prefer the equality operator when searching for a constant value such as `xxxxxx`.
Optimal indexes for this query:
CREATE INDEX table1_idx_name_isdeleted ON Table1 (Name,IsDeleted);
CREATE INDEX table2_idx_deviceid_table1id ON Table2 (DeviceId,Table1Id);
The optimized query:
LEFT OUTER JOIN
ON Table1.Id = Table2.Table1Id
AND Table2.DeviceId = 4
Table1.Name = 'xxxxxx'
AND Table1.IsDeleted = 0