please could you help me with a loop

[ricky spires]

Hello .

 

im having trouble with a loop.

i want the title to only appear ones and have the items listed under each title but it seems to be echoing the title more than once.

 

 

i want to output something like this:

 

Category1

item1

 

Category2

item1

item2

 

etc...

 

but im getting this:

 

Category1

item1

 

Category2

item1

item2

 

Category2

item1

item2

 

 

 

in my database i have this:

 

id - book_id - cat - item

1 - 1 - cat1 - item1

2 - 1 - cat2 - item1

3 - 1 - cat2 - item2

 

 

 

my loop looks like this:

 

 

//this part finds the categories by book id.

$book_id = "1";
$bookCats = Categories::find_by_book($book_id);


//this part finds the books categories

foreach($bookCats as $bookCat){
$cat_name = $bookCat->category;

echo $cat_name;

//then in put the rest of the code here.....

}

 

this is how part of the class looks

 

 public static function find_by_book($book_id) {
 return self::find_by_sql("SELECT * FROM ".self::$table_name." WHERE book_id={$book_id}");
}

 

 

 

the above code gives me:

 

cat1

cat2

cat2

 

 

i want it to only give me

 

cat1

cat2

 

 

 

 

thanks

ricky

[Barand]

Book_id "1" is in all three records, cat1/cat2/cat2.

 

Try

 

SELECT DISTINCT cat FROM ....

[ricky spires]

thanks . looks like a good direction to investigate.

 

p.s. there could be any number of book id's

 

i.e:

 

id - book_id - cat - item

1 - 1 - cat1 - item1

2 - 1 - cat2 - item1

3 - 1 - cat2 - item2

4 - 2 - cat1 - item1

5 - 3 - cat1 - item1

6 - 3 - cat2 - item2

[ricky spires]

Yipppeeeee. It worked:)

 

 

  public static function find_by_book($book_id) {
 return self::find_by_sql("SELECT DISTINCT cat FROM ".self::$table_name." WHERE book_id={$book_id} group by cat");
}

[The Letter E]

Yipppeeeee. It worked:)

 

 

  public static function find_by_book($book_id) {
 return self::find_by_sql("SELECT DISTINCT cat FROM ".self::$table_name." WHERE book_id={$book_id} group by cat");
}

 

FYI, SELECT DISTINCT, is much higher overhead and should be avoided if possible, especially on large (hundres of thousands of records) databases; Make sure to run "EXPLAIN" on your sql to check for any performance hits, like using temporary and using filesort.