如何进行 SQL 查询以获取数据字段的总和

Question

I have two tables as 1st one is " stock " and 2nd one is " parts "

stock table data fields are

id | part_id | qty | status

parts table data fields are

id | partName | status

I coded for find sum of the qty field in the same part id.

That query as follows.

SELECT `stock`.`idstock`, `parts`.`partName`, SUM(`stock`.`qty`)
FROM `stock` INNER JOIN
     `parts` 
     ON `parts`.`id` = `stock`.`part_id`
WHERE `stock`.`statu`='1'

But this query is not running correctly.

I need to show sum of the qty data field for same part id as a list.

Answer 1

From what I understand you're trying to get the sum of quantities by part. If so, it makes no sense to have stock.idstock in the select list, and you'll need a group by clause.

Try this:

SELECT parts.id, parts.partName, sum(stock.qty)
FROM stock
INNER JOIN parts on stock.part_id = parts.id
WHERE stock.status = '1'
GROUP BY parts.id, parts.partName