Update multiple tables in one query, in MySQL

Question

I want update my tables from csv. Now data from csv are imported to table "temp_update_stany", but i cant update tables. Query with no errors, but nothing is updated.

Table from CSV is:

produkt|quantity|price|active|czas

Query:

UPDATE lp2_product tabela 
        INNER JOIN lp2_stock_available stany ON (tabela.id_product = stany.id_product)
        INNER JOIN lp2_product_lang lang ON (tabela.id_product = lang.id_product)
        INNER JOIN temp_update_stany csv ON (tabela.id_product = csv.produkt)
    SET
        tabela.active = csv.active,
        tabela.price = csv.price,
        lang.available_now = csv.czas,
        stany.quantity = csv.quantity
    WHERE
        csv.produkt = tabela.id_product 
        OR csv.produkt = lang.id_product 
        OR csv.produkt = stany.id_product

and output from query:

Modified records: 0 (Perform queries took 0.0322 seconds (s)).

but for example "lp2_product" /row 'active' have value 0 for all products and temp_update_stany have value 1 for all.

Yes, this is prestashop and simple script for update quantity and prices.

Answer 1

As per comments above, the UPDATE reports zero rows affected if there is no net change. So if the tables are already updated with the desired values, the UPDATE is a no-op and no rows are "affected."