How to populate a table with a range of dates?

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夕颜
夕颜 2020-11-22 04:24

I need a MySQL table to hold ALL DATES between 2011-01-01 and 2011-12-31. I have created a table with one column names \"_date\", type DATE.

With what query can I po

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  • 2020-11-22 05:19

    Inspired by IvanD`s great number join i come to this:

    SELECT DATE_ADD('2015-10-21', INTERVAL c.number DAY)    AS DATE
    FROM 
    (
        SELECT singles + tens + hundreds+thousands number FROM 
        ( 
            SELECT 0 singles
            UNION ALL SELECT   1 UNION ALL SELECT   2 UNION ALL SELECT   3
            UNION ALL SELECT   4 UNION ALL SELECT   5 UNION ALL SELECT   6
            UNION ALL SELECT   7 UNION ALL SELECT   8 UNION ALL SELECT   9
        ) singles JOIN 
        (
            SELECT 0 tens
            UNION ALL SELECT  10 UNION ALL SELECT  20 UNION ALL SELECT  30
            UNION ALL SELECT  40 UNION ALL SELECT  50 UNION ALL SELECT  60
            UNION ALL SELECT  70 UNION ALL SELECT  80 UNION ALL SELECT  90
        ) tens  JOIN 
        (
            SELECT 0 hundreds
            UNION ALL SELECT  100 UNION ALL SELECT  200 UNION ALL SELECT  300
            UNION ALL SELECT  400 UNION ALL SELECT  500 UNION ALL SELECT  600
            UNION ALL SELECT  700 UNION ALL SELECT  800 UNION ALL SELECT  900
        ) hundreds
         JOIN 
        (
            SELECT 0 thousands
            UNION ALL SELECT  1000 UNION ALL SELECT  2000 UNION ALL SELECT  3000
            UNION ALL SELECT  4000 UNION ALL SELECT  5000 UNION ALL SELECT  6000
            UNION ALL SELECT  7000 UNION ALL SELECT  8000 UNION ALL SELECT  9000
        ) thousands
        ORDER BY number DESC
    ) c  
    WHERE c.number BETWEEN 
    0 
    AND
    DATEDIFF('2016-10-08', '2015-10-21')
    
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  • 2020-11-22 05:21

    I did not want my SQL query to require external dependencies (needing to have a calendar table, procedure for populating a temporary table with dates, etc.) The original idea for this query came from http://jeffgarretson.wordpress.com/2012/05/04/generating-a-range-of-dates-in-mysql/ which I had slightly optimized for clarity and ease of use.

    SELECT (CURDATE() - INTERVAL c.number DAY) AS date
    FROM (SELECT singles + tens + hundreds number FROM 
    ( SELECT 0 singles
    UNION ALL SELECT   1 UNION ALL SELECT   2 UNION ALL SELECT   3
    UNION ALL SELECT   4 UNION ALL SELECT   5 UNION ALL SELECT   6
    UNION ALL SELECT   7 UNION ALL SELECT   8 UNION ALL SELECT   9
    ) singles JOIN 
    (SELECT 0 tens
    UNION ALL SELECT  10 UNION ALL SELECT  20 UNION ALL SELECT  30
    UNION ALL SELECT  40 UNION ALL SELECT  50 UNION ALL SELECT  60
    UNION ALL SELECT  70 UNION ALL SELECT  80 UNION ALL SELECT  90
    ) tens  JOIN 
    (SELECT 0 hundreds
    UNION ALL SELECT  100 UNION ALL SELECT  200 UNION ALL SELECT  300
    UNION ALL SELECT  400 UNION ALL SELECT  500 UNION ALL SELECT  600
    UNION ALL SELECT  700 UNION ALL SELECT  800 UNION ALL SELECT  900
    ) hundreds
    ORDER BY number DESC) c  
    WHERE c.number BETWEEN 0 and 364
    

    It is simple to optimize and scale this table for other uses. You can easily get rid of the tens and hundreds tables if you only need one week of data.

    If you need a larger set of numbers, it is easy to add a thousands table. You only need to copy and paste the table with hundreds and add a zero to 9 numbers.

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  • 2020-11-22 05:23

    This can be achieved in PHP by using a simple for loop. There are a couple of ways to do it. One way would be to to place the original date in a variable and have the loop run through it for every day by adding +1 day on each loop, for instance, you'll start on 01/01/2011 and then the loop will add 0 the first time, 1 day the next, followed by 2 days so forth and so forth to the $i variable. You could then print out the days or add them to your database. In this case $i would represent the counter with 0 being the starting point, <=365 is how many loops you want to go through which is equal to or less than the number of days and $i++ adds +1 to the $i variable on each loop.

    date('Y-m-d' converts the date into yyyy-mm-dd. Using a capital Y gives you a full 4 digit year whereas using a lower case y will give you the last 2 digits of the year. You want to keep it in this order to add it in a date field in mySQL.

    strtotime($originalDate parses the date into a Unix time stamp and the ."+".$i." day") basically adds the value of $i in days to the date.

    Finally there's the mysqli query. $db represents the database connection variable, this will need to be changed to whatever variable you have set for the connection. This is followed by the actual query. Just exchange the word table for your table name and the date before VALUES to you date row name and you're ready to go.

    The following is an example:

    <?php
    for($i=0;$i<=365;$i++){ 
    $originalDate = "01/01/2011";
    $date = date('Y-m-d',strtotime($originalDate . "+".$i." day"));
    mysqli_query($db, "INSERT INTO table (date)VALUES('$date')");
    }
    

    Another way to achieve this using the for function would be to include the strtotime dates directly in the for actions as an oppose to the counter variables, which is an even shorter piece of code. Replace $i=0 (the starting counter point) with the starting day point, follow that with the less than or equal to the end day point (the number of loops) then finally with your plus +1 to the first statement placed into a variable ready for use.

    Finally, convert the date into Y-m-d format ready to be placed into the database and run the query.

    Again, as with the first example, this can be printed or placed directly into your database.

    The following is an example:

    <?php
    for ($startdate = strtotime("2011-01-01"); $startdate <= strtotime("2011-12-31"); $startdate = strtotime("+1 day", $startdate)) {
    $date= date("Y-m-d", $startdate);
    mysqli_query($db, "INSERT INTO tracking (date)VALUES('$date')");
    }
    

    I've probably made it sound more confusing than it is, but hope it will at least give you an idea on how it works.

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  • 2020-11-22 05:24
    INSERT INTO my_dates (\`_date\`) SELECT DATE_ADD('2011-01-01', INTERVAL @_tmp:=@_tmp+1 day) \`_date\`
    FROM (SELECT @_tmp:=-1 d UNION SELECT 1 UNION SELECT 2 
          UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6
          UNION SELECT 7 UNION SELECT 8  UNION SELECT 9) a /\*10^1\*/
    JOIN (SELECT 0 UNION SELECT 1 UNION SELECT 2 
          UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6
          UNION SELECT 7  UNION SELECT 8  UNION SELECT 9) b /\*10^2\*/
    JOIN (SELECT 0 UNION SELECT 1 UNION SELECT 2
          UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6
          UNION SELECT 7  UNION SELECT 8  UNION SELECT 9) c /\*10^3\*/
    WHERE @_tmp+1 BETWEEN 0 AND DATEDIFF('2011-12-31', '2011-01-01');
    
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