如何将时间存储为天跨度..as整数？

Question

I had a table structure as follows.. column SrNo Arrival_Time and Day. I want desired output as Day column in following pattern... How to store that? Using mysql query or php code snippet...? Day value should be in integer format. Any help will be appreciated. Thanks in advance.

CREATE TABLE `travel_time` (
  `id` int(11) NOT NULL auto_increment,
  `SrNo` int(3) default NULL,
  `Arrival_Time` time default NULL,
  `Day` int(1) default NULL,
  PRIMARY KEY  (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=61 ;

--
-- Dumping data for table `travel_time`
--

INSERT INTO `travel_time` (`id`, `SrNo`, `Arrival_Time`, `Day`) VALUES
(1, 1, '18:25:00', 1),
(2, 2, '19:50:00', 1),
(3, 3, '21:22:00', 1),
(4, 4, '22:23:00', 1),
(5, 5, '23:18:00', 1),
(6, 6, '00:30:00', 2),
(7, 7, '02:38:00', 2),
(8, 8, '03:20:00', 2),
(9, 9, '04:13:00', 2),
(10, 10, '04:53:00', 2),
(11, 11, '05:20:00', 2),
(12, 12, '06:55:00', 2),
(13, 13, '08:37:00', 2),
(14, 14, '10:10:00', 2),
(15, 15, '11:05:00', 2),
(16, 16, '11:22:00', 2),
(17, 17, '12:06:00', 2),
(18, 18, '13:22:00', 2),
(19, 19, '14:03:00', 2),
(20, 20, '14:40:00', 2),
(21, 21, '16:30:00', 2),
(22, 22, '17:28:00', 2),
(23, 23, '18:20:00', 2),
(24, 24, '19:15:00', 2),
(25, 25, '20:00:00', 2),
(26, 26, '21:18:00', 2),
(27, 27, '22:53:00', 2),
(28, 28, '23:51:00', 2),
(29, 29, '01:52:00', 3),
(30, 30, '04:10:00', 3),
(31, 1, '21:50:00', 1),
(32, 2, '23:30:00', 1),
(33, 3, '01:25:00', 2),
(34, 4, '02:27:00', 2),
(35, 5, '03:55:00', 2),
(36, 6, '05:45:00', 2),
(37, 7, '05:55:00', 2),
(38, 8, '06:43:00', 2),
(39, 9, '07:43:00', 2),
(40, 10, '09:00:00', 2),
(41, 11, '10:45:00', 2),
(42, 12, '11:40:00', 2),
(43, 13, '12:06:00', 2),
(44, 14, '13:37:00', 2),
(45, 15, '14:13:00', 2),
(46, 16, '14:29:00', 2),
(47, 17, '15:40:00', 2),
(48, 18, '16:43:00', 2),
(49, 19, '18:22:00', 2),
(50, 20, '19:22:00', 2),
(51, 21, '19:49:00', 2),
(52, 22, '20:24:00', 2),
(53, 23, '21:20:00', 2),
(54, 24, '21:53:00', 2),
(55, 25, '23:50:00', 2),
(56, 26, '01:13:00', 3),
(57, 27, '02:08:00', 3),
(58, 28, '03:27:00', 3),
(59, 29, '05:05:00', 3),
(60, 30, '06:50:00', 3);

Answer 1

I managed to get the query working, after about 45 minutes of work. Here it is:

SELECT id, SrNo, Arrival_Time,
    @day := if(m2 = 1, 1, if(m1 = 1, @day + 1, @day)) AS Day
FROM
(
    SELECT
        t1.id,
        t1.SrNo,
        t1.Arrival_Time,
        CASE WHEN t1.Arrival_time < t2.Arrival_time THEN 1 ELSE 0 END AS m1,
        CASE WHEN t1.SrNo < t2.SrNo THEN 1 ELSE 0 END AS m2
    FROM travel_time t1
    LEFT JOIN travel_time t2
        ON t1.id = t2.id + 1
) t1, (SELECT @day:=1) AS t
ORDER BY id;

Demo

The inner query, aliased as t1 , selects all data columns, along with two markers, m1 and m2 . The m1 marker keeps track of whether we have rolled over to a new day, in which case the day needs to be incremented by one. The m2 marker keeps track of whether we have reset the SrNo sequence, in which case the day also needs to be reset to 1.

Big lesson learned: We have to first materialize the self join before attempting to iterate with a user variable. Without the t1 subquery trick, my solution kept failing. Check the demo below to see this in action.

Edit:

If you need an actual table which contains this data, then I recommend using INSERT INTO ... SELECT with my query:

INSERT INTO travel_time_new (id, SrNo, Arrival_Time, Day)
SELECT ...    -- my query from above

This requires creating a new table called travel_time_new which also contains a new column for the day. You may then delete the original travel_time table, and then rename the new table to the old one.

I suggest this because updating your current table using my answer would require joining to my query, and that might have caveats as it is using user variables.

Answer 2

According to this question : how to calculate travel time using source and destination times? I think you need a PHP script for this.

I wrote a code that you can set the time and run script.Then the Time you have set will be inserted to table. This code doesn't recognize if the hour is passed 23:59 because it will ruin the table since there is nothing more than 23:51 in your table and it's working! This code just checks if the input time is after or before the last entered time in table then changes the day.

I hope this is the code you are looking for:

<?php
$insertTime="07:10";
//Connect to Database
$conn=new mysqli($dbhost,$dbuser,$dbpass,$dbname);
if (!$conn) {
die("Error Connecting To Database: ".mysqli_connect_error()."<br/>");
}
$readlastdate="SELECT * FROM travel_time  ORDER BY `travel_time`.`id` DESC";
$readresult=mysqli_query($conn,$readlastdate);
while ($row=mysqli_fetch_assoc($readresult)) {
$time=date("H:i:s",strtotime($row['Arrival_Time']));
$readDay=$row['Day'];
$TimeToInsert=date("H:i:s",strtotime($insertTime));

if ($TimeToInsert < $time) {
    $insertday=$readDay+1;
        $sql="
        INSERT INTO travel_time (`SrNo`,`Arrival_Time`,`Day`)
        VALUES ('".($row['SrNo']+1)."','".$TimeToInsert."','".$insertday."' )
        ";
        if (mysqli_query($conn,$sql)) {
            break;
        }else{echo mysqli_error($conn)."<br/>";}
}else{
    $elsesql="INSERT INTO travel_time (`SrNo`,`Arrival_Time`,`Day`)
    VALUES ('".($row['SrNo']+1)."','".$TimeToInsert."','".$readDay."' )
    ";
}
}
?>

I hope this helps you

PS:edit the database information