PHP - MYSQL - 删除重复的行，但保留最后添加的行

Question

如何删除重复的行但保留最后一行。

表

Name   Surname   Value      Date
A        AA        2     2014-10-01
B        BB        5     2014-12-01
C        CC        9     2015-07-01
D        DD        9     2016-10-01
E        EE        9     2014-10-25

重复值

Name   Surname   Value      Date
C        CC        9     2015-07-01
D        DD        9     2016-10-01
E        EE        9     2014-10-25

我想保留的价值

Name   Surname   Value      Date
D        DD        9     2016-10-01

答案后更新的代码，目标已实现。 感谢所有受访者。 我希望这对某人有用。

更新

    <?php
        include("conf.php");
        $table = "tables123";

        $query = "SELECT Name FROM " . $table;
        $resultat = mysqli_query($conn,$query);

        if(empty($resultat)) {
            echo "<p>" . $table . " table does not exist</p>";
            $query = mysqli_query($conn,"CREATE TABLE IF NOT EXISTS $table (
                Name varchar(255) NOT NULL,
                Surname varchar(255) NOT NULL,
                Value varchar(255) NOT NULL,
                Date varchar(255) NOT NULL
            )CHARACTER SET utf8 COLLATE utf8_general_ci");
        }
        else {
            echo "<p>" . $table . "table exists</p>";
        } // else

        $sql = "INSERT INTO $table (Name, Surname, Value, Date) 
        VALUES 
            ('A', 'AA', 2, '2014-10-01'), 
            ('B', 'BB', 5, '2014-12-01'), 
            ('C', 'CC', 9, '2015-07-01'), 
            ('D', 'DD', 9, '2016-10-01'),
            ('E', 'EE', 9, '2014-10-25')
            ";


        if ($conn->query($sql) === TRUE) {
            echo "New record created successfully";
        } else {
            echo "Error: " . $sql . "<br>" . $conn->error;
        }


        /// Hakan SONMEZ solution
        $sql3 = mysqli_query($conn, "
    DELETE tbl1 FROM $table tbl1, $table tbl2 WHERE tbl1.date < tbl2.date AND tb1.value = tb2.value
        ");

        ?>

Answer 1

试试这个。

DELETE tbl1 FROM new_table tbl1, new_table tbl2 WHERE tbl1.date < tbl2.date AND tbl1.value = tbl2.value;

编辑：在尝试之前复制数据。

Answer 2

这些方面的内容应该有效：

delete t from table t 
join (select value, max(Date) maxdate, from table group by value) as t1
on t.value=t1.value 
where date<maxdate