[RESOLVED] Single Table, Sort Results by Category

bronzino

My table "Pages_CSS" looks like this:

Key 	        int(11) 		
ClassID 	text 	 	
Content 	longtext

It's a table that will output CSS, where "ClassID" is a CSS class or ID, and "Content a single CSS setting like "color: #FFFFFF". A ClassID may be repeated multiple times in the table, because I may have multiple pieces of Content for it.

Given the subject matter, naturally the format I want to output is:

ClassID1
Content
Content

ClassID2
Content
Content

The closest I got to output ordered as I would like was:

$query_Style = "SELECT DISTINCT ClassID from Pages_CSS UNION Select Content from Pages_CSS order by ClassID";
$Style = mysql_query($query_Style, $CollectionLocal) or die(mysql_error());
$row_Style = mysql_fetch_assoc($Style);

That yielded results like this:

ClassID1
ClassID2
Content
Content
Content
Content

In other words, the only thing it accomplished was avoiding repetition of ClassID1 and ClassID2 over and over, with each Content row.

Do I need to create two temporary tables and join them on ClassID? If so, can someone point me at an example where this is being done from data in a single table? Every example I'm finding involves multiple tables and that is confusing.

Thanks. 🙂

bradgrafelman

Why can't you just do:

Select Content from Pages_CSS order by ClassID

bronzino

Thanks for your response.

I want it to also output ClassID, and I don't want it to repeat ClassIDs.

For example, Pages_CSS Table looks like this:

I would like it to output:

.nav
color: #FFFFFF
font-family: Georgia

.dev
color: #000000
font-family: Arial

bradgrafelman

Again, the query above will do exactly that. It's MySQL's job to return the information you want (and optionally in the order that you want) - it's not MySQL's job to format (at least, not always) and display it exactly as you'd like it. Use PHP for that.

For example, you could use a temporary variable to retain the value of ClassID from the previous loop (I'm assuming you're looping through the SQL result set, e.g. a while() loop). If it is the same, then don't print it (again). If it's different, print the new value and also store it in that temp variable for the next iteration to compare against.

bronzino

Yes, it's a while() loop that I am using for results.

I'll try my hand at getting the results formatted so that it appears as I would like. I'm assuming I'm using an "if" statement to compare the value of the Class ID from the previous loop to the next one? I've never compared "loops" before, nor employed temporary variables so this will be interesting. Will come back and start another thread if I get stuck on syntax.

Thanks brad!

bradgrafelman

bronzino wrote:
I've never compared "loops" before so this will be interesting

You can't compare a "loop" to anything; a loop is a control structure, it has no value of any kind to speak of.

What you'll be comparing is the value of the current row's ClassID attribute to the row that you previously outputted. In order to access the latter, you simply need to store it in a temporary variable before the end of the loop and use that stored value for the comparison.

bronzino

bradgrafelman;10982289 wrote:
What you'll be comparing is the value of the current row's ClassID attribute to the row that you previously outputted.

Yes, I understood what you meant even if my nomenclature was imprecise.

Thanks again.