php - 在 mysql 数据库表中令人困惑

Question

我有点混淆将结果放入两个表中，我知道这很简单，但没有任何线索.. 这是我的查询，它给了我结果，但是当我使用时，group by它只是给了我结果一行甚至数据库中的实际结果是 (300, 500) 因为我正在通过lead_id两个表中常见的结果来获取结果..

SELECT inv.amount, crmd.computers, crmd.product_id, crmd.pc_opti
FROM invoice AS inv, lead_crm_data AS crmd
WHERE inv.lead_id = '310'
AND crmd.lead_id = '310'
GROUP BY inv.lead_id

这是给定查询的结果..

amount  computers   product_id  pc_opti
300     2           7, 6            2
300     3           7, 6            3
540     2           7, 6            2
540     3           7, 6            3

结果与GROUP BY

300     2           7, 6            2

期望的结果

300     2           7, 6            2
540     3           7, 6            3

Answer 1

试试这个：

SELECT inv.amount, crmd.computers, crmd.product_id, crmd.pc_opti
FROM invoice AS inv, lead_crm_data AS crmd
WHERE inv.lead_id = '310'
  AND crmd.lead_id = '310'
GROUP BY inv.amount

您可以使用更好的（恕我直言）语法：

SELECT inv.amount, crmd.computers, crmd.product_id, crmd.pc_opti
FROM invoice AS inv INNER JOIN lead_crm_data AS crmd 
    ON inv.lead_id = crmd.lead_id 
   AND inv.lead_id = '310'
GROUP BY inv.amount