MYSQL：每組最多n個問題

Question

greatest-n-per-group問題和我的MySQL版本無法使用LIMIT＆IN（錯誤1235），因此我需要使用這種查詢（請參見此處的答案 ： answer ）

SELECT
                t1.idMemberCard,
                DATE(MIN(transactions.dateTransaction)) AS first_transaction,
                DATE(MAX(transactions.dateTransaction)) AS last_transaction,
                t2.*
                FROM membersCard AS t1
                INNER JOIN transactions ON transactions.idMemberCard = t1.idMemberCard
                INNER JOIN
                (
                    SELECT
                        membersCard.idMemberCard,
                        membersCard.cardNumber,
                        membersCard.firstNameMemberCard,
                        membersCard.lastNameMemberCard,
                        transactions.dateTransaction
                    FROM membersCard
                    INNER JOIN transactions ON transactions.idMemberCard = membersCard.idMemberCard
                    WHERE membersCard.sexMemberCard = 'M'
                    AND membersCard.cardNumber = '1100101308655'
                    AND
                    DATE(transactions.dateTransaction) BETWEEN ('2013-12-28') AND ('2014-08-13')
                    LIMIT 100
                ) AS t2
                ON t1.idMemberCard = t2.idMemberCard

為完全匹配（卡號）而執行的子查詢（t2表）恰好返回5行（在此示例中）：全部完美。

我的問題/要求：

將兩個表連接在一起，我將獲得5行，而不僅是5行，而5行帶有日期。

Answer 1

您的join工作正常。 問題是您的select語句：

 SELECT t1.idMemberCard,
        DATE(MIN(transactions.dateTransaction)) AS first_transaction,
        DATE(MAX(transactions.dateTransaction)) AS last_transaction,
        t2.*

MIN()和MAX()將其變成聚合查詢，該查詢僅返回一行。 嘗試這個：

 SELECT t1.idMemberCard,
        DATE(transactions.dateTransaction) AS first_transaction,
        DATE(transactions.dateTransaction) AS last_transaction,
        t2.*

或者group by如果需要，可以添加group by子句。