我确定有一种方法可以enswitch_mobile_users
更好地提取数据,而不是我如何提取数据
Enswitch_User_ID、Os_Version、Phone_Type
那么如何改进和改进这个查询呢?
$sql = "SELECT Substring(purchase.`date`,12,8) AS `Time`,
purchase.`item` AS `Package`,
Cast(Substring(purchase.`item`, 12) AS UNSIGNED) AS `Credit`,
purchase.`user` AS `Mobile_User_ID`,
(SELECT user_id FROM enswitch_mobile_users WHERE `Mobile_User_ID` = enswitch_mobile_users.`id`) AS `Enswitch_User_ID`,
(SELECT os_version FROM enswitch_mobile_users WHERE `Mobile_User_ID` = enswitch_mobile_users.`id`) AS `Os_Version`,
(SELECT phone_type FROM enswitch_mobile_users WHERE `Mobile_User_ID` = enswitch_mobile_users.`id`) AS `Phone_Type`,
(SELECT enswitch_id FROM enswitch_users WHERE `Enswitch_User_ID` = enswitch_users.`id`) AS `Enswitch_ID`
FROM (SELECT item, date, user
FROM enswitch_android_purchases
UNION
SELECT item, date, user
FROM enswitch_iphone_purchases) AS `purchase`
WHERE Substring(purchase.`date`,1,10) = :date
ORDER BY `Time` DESC";