Mysql嵌套查询速度非常慢

Question

我有一个名为vehicle_plate的表，如下所示：

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上表的总记录是715210，我希望在特定区域和省份按最新或更新的车牌类型对车辆进行计数，但是当我运行以下查询时，查询速度非常慢。我的意思是，我从来没有得到结果，它只是装载。

            SELECT `pt`.`pt_dr` AS
            TYPE , COUNT( DISTINCT vp.vehicle_v_id ) AS vehicles, `p`.`province_dr` AS province_name, `p`.`id` AS id, vp.vehicle_v_id
            FROM (
            `vehicle_plate` AS vp
            )
            LEFT JOIN provinces AS p ON p.id = vp.provinces_province_id
            LEFT JOIN plate_types AS pt ON pt.id = vp.plate_types_pt_id
            WHERE 1
            AND p.zone_zone_id = '1'
            AND p.id = '1'

            AND vp.id
            IN (

            SELECT vp1.id
            FROM vehicle_plate AS vp1
            GROUP BY vp1.vehicle_v_id
            )
            GROUP BY vp.vehicle_v_id, `vp`.`plate_types_pt_id`
            ORDER BY `p`.`zone_zone_id` , `vp`.`provinces_province_id` , `vehicles` DESC

注意：一辆车可能有多个车牌，我想数一下最新的板块类型。

样本数据：

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Answer 1

有时，内部联接比in子句更具有性能。

      SELECT `pt`.`pt_dr` AS
        TYPE , COUNT( DISTINCT vp.vehicle_v_id ) AS vehicles, `p`.`province_dr` AS province_name, `p`.`id` AS id, vp.vehicle_v_id
        FROM (
        `vehicle_plate` AS vp
        )
        LEFT JOIN provinces AS p ON p.id = vp.provinces_province_id
        LEFT JOIN plate_types AS pt ON pt.id = vp.plate_types_pt_id
        INNER JOIN   (

        SELECT vp1.id as id
        FROM vehicle_plate AS vp1
        GROUP BY vp1.vehicle_v_id
        ) t on vp.id  = t.id 
        WHERE 1
        AND p.zone_zone_id = '1'
        AND p.id = '1'

        GROUP BY vp.vehicle_v_id, `vp`.`plate_types_pt_id`
        ORDER BY `p`.`zone_zone_id` , `vp`.`provinces_province_id` , `vehicles` DESC