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 SELECT   CASE      WHEN type = 'allocated' THEN car_no     ELSE (SELECT car_no FROM tbl_booked_car_details b2            WHERE b2.tbl_booking_details_primary_id = bd.tbl_booking_details_primary_id              AND b2.type = 'allocated'              ORDER BY allocation_from_date DESC              LIMIT 1)   END AS car_no,    car_no as served_car,   allocation_from_date,   allocation_to_date FROM tbl_booked_car_details bd ORDER BY car_no, allocation_from_date;

 SELECT      t1.car_no,     SUM(DATEDIFF(FROM_UNIXTIME(t1.allocation_to_date), FROM_UNIXTIME(t1.allocation_from_date)) + 1) AS total_days_booked,     SUM(         CASE             WHEN t2.allocation_to_date IS NOT NULL THEN                  DATEDIFF(FROM_UNIXTIME(t1.allocation_from_date), FROM_UNIXTIME(t2.allocation_to_date)) - 1             ELSE                  0         END     ) AS missing_days FROM      tbl_booked_car_details t1 LEFT JOIN      tbl_booked_car_details t2 ON t1.car_no = t2.car_no AND FROM_UNIXTIME(t1.allocation_from_date) > FROM_UNIXTIME(t2.allocation_to_date) GROUP BY      t1.car_no;

  SELECT   d .aggregator_id ,   d .model_id ,   CASE   WHEN   COUNT ( r .tbl_demo_p_id )   =   d .quantity   THEN   'Full'   ELSE   'Empty'   END   AS   status   FROM   tbl_demo   d   LEFT   JOIN   tbl_demo_refer   r   ON   d .id   =   r .tbl_demo_p_id   WHERE   d .aggregator_id   =   1   AND   d .model_id   =   2   GROUP   BY   d .aggregator_id ,   d .model_id ,   d .quantity ; SELECT      d.aggregator_id,     d.model_id,     CASE          WHEN COUNT(r.tbl_demo_p_id) = d.quantity THEN 'Full'         ELSE 'Empty'     END AS status FROM      tbl_demo d LEFT JOIN      tbl_demo_refer r ON d.id = r.tbl_demo_p_id WHERE      d.aggregator_id = <aggregator_id_value>     AND d.model_id = <model_id_value>     AND r.car_no = '<car_no_value>' GROUP BY      d.aggregator_id, d.model_id, d.quantity;