我有一个庞大的项目,我需要进行统计。此查询为我提供了准确的结果,但加载时有点慢,需要以某种方式优化,但无法弄清楚如何。
SELECT
TRIM(`op`.`products_quantity`) AS `products_quantity`,
TRIM(`op`.`products_price`) AS `products_price`,
TRIM(`op`.`orders_products_status`) AS `orders_products_status`,
TRIM(`p`.`product_type`) AS `product_type`,
IF(`p`.`product_type` IN ('G'),FLOOR(`op`.`final_price`*`op`.`products_quantity`),
`op`.`final_price`) AS `final_price`,
TRIM((
SELECT
`o`.`payment_method`
FROM
`orders` `o`
WHERE
`o`.`orders_id` = `op`.`orders_id`
GROUP BY `o`.`orders_id`
)) AS `payment_method`,
IF(
TRIM(DATE_FORMAT(STR_TO_DATE(`cd`.`concert_date`,'%d/%m/%Y'),'%d/%m/%Y')) LIKE (
SELECT
TRIM(DATE_FORMAT(`o`.`date_purchased`,'%d/%m/%Y'))
FROM
`orders` `o`
WHERE
`o`.`orders_id` = `op`.`orders_id`
GROUP BY `o`.`orders_id`
),
1,0
) AS `same_day`
FROM
`categories` `c`,
`categories_description` `cd`,
`products` `p`,
`orders_products` `op`
WHERE
`c`.`section_id` = 25
AND
`cd`.`categories_id` = `c`.`categories_id`
AND
`p`.`section_id` = `c`.`section_id`
AND
`p`.`product_type` IN ('P')
AND
`op`.`products_id` = `p`.`products_id`
GROUP BY `op`.`orders_products_id`
ORDER BY `payment_method` ASC
有人有什么建议吗?
我还想从SQL专家那里得到一些很好的解释,如何组织类似查询的最佳方式以及首先需要在WHERE
部分内部进行查询。
答案 0 :(得分:2)
您可以通过使用 JION
加入所有表格来更好地执行此操作试试这样: -
SELECT
TRIM(`op`.`products_quantity`) AS `products_quantity`,
TRIM(`op`.`products_price`) AS `products_price`,
TRIM(`op`.`orders_products_status`) AS `orders_products_status`,
TRIM(`p`.`product_type`) AS `product_type`,
IF(`p`.`product_type` IN ('G'),FLOOR(`op`.`final_price`*`op`.`products_quantity`),
`op`.`final_price`) AS `final_price`,
TRIM((
SELECT
`o`.`payment_method`
FROM
`orders` `o`
WHERE
`o`.`orders_id` = `op`.`orders_id`
GROUP BY `o`.`orders_id`
)) AS `payment_method`,
IF(
TRIM(DATE_FORMAT(STR_TO_DATE(`cd`.`concert_date`,'%d/%m/%Y'),'%d/%m/%Y')) LIKE (
SELECT
TRIM(DATE_FORMAT(`o`.`date_purchased`,'%d/%m/%Y'))
FROM
`orders` `o`
WHERE
`o`.`orders_id` = `op`.`orders_id`
GROUP BY `o`.`orders_id`
),
1,0
) AS `same_day`
FROM
`categories` `c`
join `categories_description` `cd` on `cd`.`categories_id` = `c`.`categories_id`
join `products` `p` on `p`.`section_id` = `c`.`section_id`
join `orders_products` `op` on `op`.`products_id` = `p`.`products_id`
WHERE
`c`.`section_id` = 25
AND
`p`.`product_type` IN ('P')
GROUP BY `op`.`orders_products_id`
ORDER BY `payment_method` ASC
答案 1 :(得分:1)
您可以尝试并运行几个基本步骤:
答案 2 :(得分:1)
由于没有数据,我无法验证查询。但我认为以下可选查询可能会有所帮助:
SELECT
TRIM(`op`.`products_quantity`) AS `products_quantity`,
TRIM(`op`.`products_price`) AS `products_price`,
TRIM(`op`.`orders_products_status`) AS `orders_products_status`,
TRIM(`p`.`product_type`) AS `product_type`,
IF(`p`.`product_type` = 'G', FLOOR(`op`.`final_price` * `op`.`products_quantity`), `op`.`final_price`) AS `final_price`,
TRIM(`t`.`payment_method`) AS `payment_method`,
IF( TRIM(DATE_FORMAT(STR_TO_DATE(`cd`.`concert_date`,'%d/%m/%Y'),'%d/%m/%Y')) LIKE
TRIM(DATE_FORMAT(`t`.`date_purchased`,'%d/%m/%Y')), 1, 0 ) AS `same_day`
FROM
`categories` `c` INNER JOIN `categories_description` `cd` ON `c`.`categories_id` = `cd`.`categories_id`
INNER JOIN `products` `p` ON `c`.`section_id` = `p`.`section_id`
INNER JOIN `orders_products` `op` ON `p`.`products_id` = `op`.`products_id`
INNER JOIN
( SELECT `o`.`orders_id`, `o`.`payment_method`,
TRIM(DATE_FORMAT(`o`.`date_purchased`,'%d/%m/%Y')) AS `date_purchased`
FROM `orders` `o` GROUP BY `o`.`orders_id` ) AS `t` ON `op`.`orders_id` = `t`.`orders_id`
WHERE `c`.`section_id` = 25 AND `p`.`product_type` IN ('P')
GROUP BY `op`.`orders_products_id`
ORDER BY `payment_method`;
请注意,以下部分对于两个内部子查询都很常见:
FROM `orders` `o`
WHERE `o`.`orders_id` = `op`.`orders_id`
GROUP BY `o`.`orders_id`
这意味着您指的是具有相同条件的同一个表两次,只是为了得到两个不同的列。所以我删除了那部分并将其添加为单个子查询的INNER JOIN
。
另请注意,IN
的括号中只有一个值。所以我已将IN
替换为=
。
如果这对您有帮助,请告诉我。