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POFaster MySQL Join for DISTINCT records
 

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    <p>After reviewing the related questions, none of them seem to address mine, so here goes:</p> <p>I have two tables containing Course information. One table [course] holds, currently, nearly 25k records with fields such as CourseName, CourseCode, Term, Instructor, etc. The second table [courseCatalog] holds merely the CourseCode and CourseName. </p> <p>My application allows users to pull up an instructor and approve the courses from a list that they are allowed to teach.</p> <p>I built a search with auto-suggest (jQuery Ajax Object -> PHP file -> MySQL and back) to find courses. When they are returned the user can click the course to mark (Another Ajax call to PHP &amp; MySQL) it as an approved course for the instructor.</p> <p>The problem is, there are some courses in the larger table that are not in the smaller table, and vice versa (eliminating that problem is a much harder issue based on where the data actually comes from, i digress)</p> <p>If I join the tables on any particular field, certain courses are left out. LEFT JOIN still seems to yield the same problem because I'm forced to JOIN ON a field.</p> <p>If I simply call to both tables:</p> <pre><code>SELECT DISTINCT course.CourseCode, course.CourseName FROM course, courseCatalog </code></pre> <p>The query takes FOREVER which renders the search function useless, as it takes to long to load the suggestions.</p> <p>I'd like to get a DISTINCT list of courses, in order, whether they appear in the 'course' table or the 'courseCatalog' table...with great haste :)</p> <p>Any suggestions? Have I overlooked something simple? Thanks all</p>
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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.

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