Finding out if there is a daily insert into mysql table - mysql

Question

I have this table which should be getting daily input regarding Vehicle mileage Readings.
CREATE TABLE `table_vehicle_info` (
`id` int(11) NOT NULL ,
`reg_no` varchar(50) NOT NULL,
`vehicle_type` int(11) NOT NULL,
`engine_no` varchar(50) NOT NULL DEFAULT "DDDD",
`chassis_no` varchar(50) ,
`model` int(11) DEFAULT NULL,
`picture` varchar(50) ,
`rent` double ,
`eng_power` int(11) DEFAULT NULL,
`color` varchar(12) DEFAULT NULL,
`rent_status` varchar(50) DEFAULT NULL,
`reg_city` varchar(50) DEFAULT NULL,
`location` varchar(50) DEFAULT NULL,
`sub_type` varchar(50) DEFAULT NULL,
`purchase_date` date DEFAULT NULL,
`purchase_amount` double DEFAULT NULL,
`sum_insured` double DEFAULT NULL,
`token_tax_amount` double DEFAULT NULL,
`token_period_from` date DEFAULT NULL,
`reg_placed_at` varchar(50) DEFAULT NULL,
`funded_by` varchar(50) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=99 DEFAULT CHARSET=latin1;
CREATE TABLE `tbl_readings` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`vehicle_id` int(11) NOT NULL,
`km_driven` int(11) NOT NULL,
`dt_of_reading` datetime NOT NULL,
`dt_of_entry` datetime NOT NULL,
`entry_user` varchar(50) NOT NULL,
PRIMARY KEY (`id`),
KEY `vehicle_id` (`vehicle_id`),
CONSTRAINT `tbl_readings_ibfk_1` FOREIGN KEY (`vehicle_id`) REFERENCES `table_vehicle_info` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB AUTO_INCREMENT=20 DEFAULT CHARSET=latin1;
INSERT INTO table_vehicle_info (id,reg_no,vehicle_type )
VALUES (1, "B-5484", 12 );
INSERT INTO tbl_readings VALUES (NULL,1,100,'2015-6-1',NOW(), 'user');
I want to generate a report showing which vehicle reading isn't entered daily.

Answer 1

You can try following query, it returns all vehicle_id from tbl_readings for which there is no next day entry.
SELECT vehicle_id
FROM `tbl_readings`
WHERE DATE(DATE_ADD(dt_of_entry,INTERVAL 1 DAY)) NOT IN
(SELECT DATE(dt_of_entry) FROM `tbl_readings`)
EDIT
Try this,
SELECT t1.vehicle_id
FROM `tbl_readings` t1
LEFT JOIN (SELECT vehicle_id,
DATE(DATE_ADD(dt_of_reading,INTERVAL -1 DAY)) as reading_date
FROM `tbl_readings`) t2
ON t1.vehicle_id = t2.vehicle_id AND t1.dt_of_reading = t2.reading_date
WHERE t2.vehicle_id IS NULL
GROUP BY t1.vehicle_id
HAVING COUNT(t1.vehicle_id) > 1;
check the fiddle