[Solved] Subquery magic in PostgreSQL

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. 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.
Optimal indexes for this query:
CREATE INDEX product_product_idx_product_id ON "product_product" ("product_tmpl_id");
CREATE INDEX product_template_idx_type ON "product_template" ("type");
The optimized query:
SELECT
        product_product.write_date,
        product_product.default_code 
    FROM
        product_product 
    WHERE
        product_product.product_tmpl_id IN (
            SELECT
                DISTINCT product_template.product_tmpl_id 
            FROM
                product_template 
            WHERE
                product_template.type = 'import'
        )

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* original question posted on StackOverflow here.