array_unique causing undefined offset error

Question

I have been trying to use array_unique to remove duplicates from the search results I am populating. However, I am getting an undefined offset error. I was wondering if anyone knows what is causing this error and what I can do to fix it? As you can see below I am populating search results from two different places and trying to merge all matches into one array.

Before array_unique: Array ( [0] => Bob Marley Footwear [1] => Bob Marley Footwear [2] => DVS Shoe Co. )

After array_unique: Array ( [0] => Bob Marley Footwear [2] => DVS Shoe Co.)

Note: this causes an error message to appear when trying to access array slot 1 when iterating through array, to print out the results.

    $results = mysql_query("SELECT keywords,name FROM files WHERE MATCH (keywords,name) AGAINST ('$searchfor')") or die(mysql_error());


    $matches=Array();
    $matches_final=Array();

    while($row = mysql_fetch_array($results)){
        $matches[] = $row['name'];
    }
    $matches_final = array_unique($matches);

    $results1 = mysql_query("SELECT name FROM files");
    while($row1 = mysql_fetch_array($results1)){
        $temp = explode(" ", $row1['name']);

        for($z=0; $z < sizeof($search_words); $z++){
            for($i=0; $i < sizeof($temp); $i++){
                if(((strcmp(strtolower($search_words[$z]), strtolower($temp[$i])))==0) and strlen($search_words[$z])<=5){
                    $matches_final[] = $row1['name'];
                }
            }
        }
    }


return $matches_final;

I might be tired, but I can't see anything that would error there. Which line is throwing the error? No possibility for using SQL's distinct here to ensure uniqueness that way? — Mitya
– Mitya, Commented Jun 30, 2012 at 23:47
the error is thrown when trying to iterate through the array to print out the array slot 1 which was removed due to using the unique_array function. — AnchovyLegend
– AnchovyLegend, Commented Jun 30, 2012 at 23:51

Rawkode · Accepted Answer · 2012-06-30 23:53:22Z

6

I'd like to first suggest you use DISTINCT(name) in your query to remove the need for array_unique.

The error is due to array_unique removing an element and not rekeying the array. You could perform array_values on your array prior to returning it to rekey.

answered Jun 30, 2012 at 23:53

Rawkode

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2 Comments

Mitya Over a year ago

Ah yes of course, well spotted. array_unique preserves keys, and, unlike some functions, has no option to change this behaviour.

AnchovyLegend Over a year ago

thanks for the help! array_values did the trick! Using mySQL DISTINCT would not work because there aren't any duplicates in my DB. The duplicates occur while populating the '$matches' array from more than one source, to cater to many different search queries, b/c mysql full-text search leaves out some search results. Appreciate the help very much:)

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