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POMerge multiple database results into one
 

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    <p>I am unsure as to what to call this question. I have been thinking a lot about it, and I do not think that what I've chosen covers it adequately, but it was the best I could manage. Forgive me if it is very misleading or incorrect.</p> <p>I am creating a small CMS for personal use, but I have stumbled upon trouble.</p> <p>The information is stored in a MySQL database, and the table has three columns: <em>cid</em>, <em>page</em> and <em>cont</em>.</p> <p>The cid is the identifier of a certain piece of content. If a <em>page</em> has multiple pieces of content, such as a main area of text and a sub area of text, the <em>cid</em> on these rows would be different, but the <em>page</em> would be the same, seeing as the content is on the same page.</p> <p>On the index page of the CMS I am then displaying all the different pages that exist in the database, as links. The user then clicks the link to the page on which he'd want to change the content.</p> <p><strong>Now, here is my issue:</strong></p> <p>When displaying the data from the database, rows that have the same page, but different <em>cid</em> is, logically, displayed as separate links.</p> <p>That sounded confusing. I'll say it differently:</p> <p><strong>What I need is that</strong> if a result has the same <em>page</em> as another result, these two are merged together into one link, and not displayed as two separate links.</p> <p>This is how the database looks:</p> <pre><code>+------------+----------+-----------------------------------------+ | cid | page | cont | +-----------------------------------------------------------------+ | page1-main | page1 | This is the first page on this website! | | page2-main | page2 | This is the second page! | | page2-sub | page2 | This is sub-content! | +------------+----------+-----------------------------------------+ </code></pre> <p>As I said, what I want is to have any rows that have the same <em>page</em> be merged into one result in my while loop, because what happens now is that they are separated into two different results. This is my loop and query:</p> <pre><code>$query = mysqli_query("SELECT * FROM content"); while($row = mysqli_fetch_array($query)) { ?&gt; &lt;a href="edit.php?p=&lt;?php echo $row['page'];?&gt;"&gt;Link!&lt;/a&gt; &lt;?php } </code></pre> <p>That will, of course, display two results, even though they have the same page. I am unsure as to whether it is some PHP I will have to do, or it is in the MySQL query. I am a good bit unexperienced in SQL, but fairly experienced in PHP.</p> <p>I've been thinking about some ifs. Like, storing every new result that is displayed in a variable and then comparing them, and if one that has occurred before occurs again, then it is not displayed, or something. But I don't know.</p> <p>It would be wonderful if anyone could help me out here.</p>
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    1. USReduxedProfessor
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    1. COtry doing SELECT * FROM content group by page
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    2. COFor improved performance, if you only need the `page` column, then ditch the "`*`" in your query, and reference just the columns you need to return. To have the rows returned in a deterministic sequence, include an ORDER BY in your query. `SELECT DISTINCT page FROM content ORDER BY page`. (A `GROUP BY` in MySQL implicitly performs an `ORDER BY`.
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      1. USspencer7593
 

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