Databases
StackOverflow2013
Postsdbo
POhow to use MySQL for a dynamic pivot table or crosstab
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POhow to use MySQL for a dynamic pivot table or crosstab
    primarykey
    data
    text
    <p>I know this question or a variance thereof has been asked multiple times, and I have even tried implementing a solution, but I am struggling in completing it.</p> <p>I have a very simple table with three data columns: Date1, Report_#, Name. I would like to pivot it around Date and the various names as the header tab, and have all the report numbers appear below. </p> <p>So it would LOOK like this:</p> <pre><code>Report | Date | Name Date | Name1 | Name2 | Name3 ----------------------- ------------------------------ 1 | 4-5-12 | Name1 4-5-12 | 1 | 2 | 3 2 | 4-5-12 | Name2 -----&gt; 4-6-12 | 4 | 5 | 6 3 | 4-5-12 | Name3 4-7-12 | 7 | 8 | 9 4 | 4-6-12 | Name1 5 | 4-6-12 | Name2 6 | 4-6-12 | Name3 7 | 4-7-12 | Name1 8 | 4-7-12 | Name2 9 | 4-7-12 | Name3 </code></pre> <p>I was able to get an idea of what to do from <a href="http://www.artfulsoftware.com/infotree/queries.php#78" rel="nofollow">http://www.artfulsoftware.com/infotree/queries.php#78</a> but I'm stuck. </p> <p>I was able to isolate the column names manually and list the report # under each name, but I want to do dynamically figure out the distinct names, make them column names, and list the corresponding reports.</p> <p>So I created a procedure that would find distinct names and output the correct code. Now I have a hard time plugging the results of the procedure onto the query. And the link above does not help whatsoever, (it seems to skip that step).</p> <p>So here is the code for the manual way:</p> <pre><code>SELECT `DATE`, GROUP_CONCAT(CASE `Name` WHEN 'Name1' THEN `Report` END) AS 'Name1', GROUP_CONCAT(CASE `Name` WHEN 'Name2' THEN `Report` END) AS 'Name2' FROM `report_db` GROUP BY `DATE` ORDER BY `DATE`; </code></pre> <p>And here is the code that dynamic prints the GROUP_CONCAT(... for all the distinct names in the database:</p> <pre><code>DROP PROCEDURE IF EXISTS writecountpivot; DELIMITER | CREATE PROCEDURE writecountpivot( db CHAR(64), tbl CHAR(64), col CHAR(64) ) BEGIN DECLARE datadelim CHAR(1) DEFAULT '"'; DECLARE singlequote CHAR(1) DEFAULT CHAR(39); DECLARE comma CHAR(1) DEFAULT ','; SET @sqlmode = (SELECT @@sql_mode); SET @@sql_mode=''; SET @sql = CONCAT( 'SELECT DISTINCT CONCAT(', singlequote, ',group_concat(IF(', col, ' = ', datadelim, singlequote, comma, col, comma, singlequote, datadelim, comma, '`IR NO`,null)) AS `', singlequote, comma, col, comma, singlequote, '`', singlequote, ') AS countpivotarg FROM ', db, '.', tbl, ' WHERE ', col, ' IS NOT NULL' ); -- UNCOMMENT TO SEE THE MIDLEVEL CODE: -- SELECT @sql; PREPARE stmt FROM @sql; EXECUTE stmt; DROP PREPARE stmt; SET @@sql_mode=@sqlmode; END | DELIMITER ; CALL writecountpivot('database','`report_db`','name'); </code></pre> <p>and the result of the code above would be this</p> <pre><code>,group_concat(IF(name = "Name1",`IR NO`,null)) AS `Name1` ,group_concat(IF(name = "Name2",`IR NO`,null)) AS `Name2` ,group_concat(IF(name = "Name3",`IR NO`,null)) AS `Name3` </code></pre> <p>** So how do I take this text and plug it to my SQL? How do I put the procedure and the query together?**</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USuser139301
    1. USuser139301
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload