MySQL:如何优化这个查询？

Question

我几乎花了一天时间来优化这个查询:

SELECT 
    prod. *, 
    cat.slug category_slug, 
    sup.bname bname, 
    sup.slug bname_slug
FROM bb_admin.bb_directory_products AS prod
LEFT JOIN bb_admin.bb_categories_products AS cat 
    ON prod.primary_category_id = cat.category_id
LEFT JOIN bb_admin.bb_directory_suppliers AS sup 
    ON prod.supplier_id = sup.supplier_id
LEFT JOIN bb_admin.bb_directory_suppliers AS credit_sup 
    ON prod.credit_supplier_id = credit_sup.supplier_id
LEFT JOIN bb_admin.bb_directory_suppliers AS photo_sup 
    ON prod.photo_supplier_id = photo_sup.supplier_id
WHERE (
    prod.status = '1'
    OR prod.status = '3'
    OR prod.status = '5'
)
    AND (
        sup.active_package_id != '1'
        OR sup.active_package_id != '5'
        OR sup.active_package_id != '6'
        OR prod.supplier_id = '0'
    )
    AND (
        sup.supplier_id = '1989'
        OR credit_sup.supplier_id = '1989'
        OR photo_sup.supplier_id = '1989'
    )
GROUP BY prod.product_id
ORDER BY prod.priority_index ASC

你能帮我优化这个查询吗？

Answer 1

1. 将列数据类型更新为 INT 或其变体之一，因为您要检查的数据类型都是整数 ID(假设)。

2. 在以下列上创建索引(如果可能的话在所有表中):

   • 产品状态
   • supplier_id
   • active_package_id
3. 使用 IN 子句而不是连接 OR 段。

我将把更新后的 WHERE 子句放在这里:

WHERE prod.status IN(1, 3, 5)
    AND ( sup.active_package_id NOT IN(1, 5, 6)
        OR prod.supplier_id = 0
    )
    AND 1989 IN (prod.supplier_id, prod.credit_supplier_id, prod.photo_supplier_id)