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    <p>I now have a name for what I'm trying to accomplish. It's a 'dynamic crosstab'. Here is how I got to the solution. Thanks to <a href="http://rpbouman.blogspot.com/2005/10/creating-crosstabs-in-mysql.html" rel="nofollow">http://rpbouman.blogspot.com/2005/10/creating-crosstabs-in-mysql.html</a> for the clear instructions for getting here.</p> <p><strong>Lines 1-20</strong> - Set up a table to use for testing.</p> <p><strong>Lines 22-29</strong> - a 'static' crosstab query, assuming I know how many requirements I've got. Thanks D Mac for the solution you gave :)</p> <p><strong>Lines 30-44</strong> - A query that dynamically generates the static query above. </p> <p><strong>Lines 45-72</strong> - This is where I’m having the problem. The intent is to create a stored procedure that returns the result of the dynamic query. MySQL is saying there is a syntax issue, but I don't see how to fix it. Any thoughts?</p> <pre><code>drop table if exists pivot; create table `pivot` ( `req_id` int(11), `testcase_id` int(11) ); /*Data for the table `pivot` */ insert into `pivot`(`req_id`,`testcase_id`) values (1,4); insert into `pivot`(`req_id`,`testcase_id`) values (2,4); insert into `pivot`(`req_id`,`testcase_id`) values (3,4); insert into `pivot`(`req_id`,`testcase_id`) values (4,7); insert into `pivot`(`req_id`,`testcase_id`) values (1,7); insert into `pivot`(`req_id`,`testcase_id`) values (2,12); insert into `pivot`(`req_id`,`testcase_id`) values (3,12); insert into `pivot`(`req_id`,`testcase_id`) values (4,4); select * from pivot; select testcase_id , if(sum(req_id = 1), 1, 0) , if(sum(req_id = 2), 1, 0) , if(sum(req_id = 3), 1, 0) , if(sum(req_id = 4), 1, 0) from pivot group by testcase_id; select concat( 'select testcase_id','\n' , group_concat( concat( ', if(sum(req_id = ',p2.req_id,'), 1, 0)','\n' ) order by p2.req_id separator '' ) , 'from pivot','\n' , 'group by testcase_id;','\n' ) statement from pivot p2 order by p2.req_id; CREATE PROCEDURE p_coverage() LANGUAGE SQL NOT DETERMINISTIC CONTAINS SQL SQL SECURITY DEFINER begin select concat( 'select testcase_id','\n' , group_concat( concat( ', if(sum(req_id = ',p2.req_id,'), 1, 0)','\n' ) order by p2.req_id separator '' ) , 'from pivot','\n' , 'group by testcase_id;','\n' ) statement into @coverage_query from pivot p2 order by p2.req_id; prepare coverage from @coverage_query; execute coverage; deallocate prepare coverage; end; select * from pivot; </code></pre>
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