How to specify target table for update in FROM clause for MYSQL?

Question

My script-:

UPDATE catalog_product_price 
SET catalog_product_price.value = 200
WHERE value_id = (
    SELECT value_id
    FROM catalog_product_price
    WHERE `entity_id` = ( 
        SELECT `entity_id` 
        FROM `catalog_product_entity` 
        WHERE `sku` LIKE 'sample'
        ) 
    AND website_id = 10
    AND customer_group_id= (
        SELECT customer_group_id
        FROM customer_group
        WHERE 
            customer_group_id = catalog_product_price.customer_group_id 
            AND customer_group_code =100
        )
    )

It gives me following error-:

#1093 - You can't specify target table 'catalog_product_price' for update in FROM clause

Can anybody provide me solution for the same as I tried solution given on this link-: http://www.mysqlfaqs.net/mysql-faqs/Errors/1093-You-can-not-specify-target-table-comments-for-update-in-FROM-clause but unable to do... Please help me..

Answer 1

You need to join tables to the UPDATE statement instead of using all of those subqueries

UPDATE  catalog_product_price cpp

JOIN    catalog_product_entity cpe
  ON    cpe.entity_id = cpp.entity_id
  AND   cpe.sku LIKE 'sample'
  AND   website_id = 10

JOIN    customer_group cg
  ON    cg.customer_group_id = cpp.customer_group_id
  AND   cg.customer_group_code = 100

SET cpp.value = 200

note: Your syntax is quite difficult to read so I may have made a mistake interpreting it. Anyway, this is the idea and it should help you get to the final answer.

Answer 2

Store the queried values in user defined variables:

set @value_id := (
    SELECT value_id
    FROM catalog_product_price
    WHERE `entity_id` = ( 
        SELECT `entity_id` 
        FROM `catalog_product_entity` 
        WHERE `sku` LIKE 'sample'
    );
set @customer_group_id := (
    SELECT customer_group_id
    FROM catalog_product_price
    WHERE `entity_id` = ( 
        SELECT `entity_id` 
        FROM `catalog_product_entity` 
        WHERE `sku` LIKE 'sample'
    );

UPDATE catalog_product_price 
SET catalog_product_price.value = 200
WHERE value_id = @value_id 
AND website_id = 10
AND customer_group_id = @customer_group_id;

Note that your second inner query is nonsense - you are selecting column customer_group_id whose value is already known because of the where clause WHERE customer_group_id = catalog_product_price.customer_group_id... completely redundant