Please PMJI, but I'm new to PHP but have a little experience with databases, 
and I have a question:
 
Is there a particular reason that LIKE is used in the query?  Let's say you had 
the contrived alias value in the table, 'aaaaa', and one wanted to add the 
alias, 'aaaa' (or fewer 'a's).  Wouldn't the query misreport that the alias, 
'aaaa', already exists?
 
I'm assuming that the number of characters in the alias can vary by some range 
(e.g., 3 to 10 characters), and that:
  "SELECT alias FROM tablename WHERE alias LIKE '$alias%' LIMIT 1";

becomes:
  "SELECT alias FROM tablename WHERE alias LIKE 'aaaa%' LIMIT 1";

at execution-time.
 
Regards,
Dave

        -----Original Message----- 
        From: Jeffrey [mailto:[EMAIL PROTECTED] 
        Sent: Sun 10/2/2005 3:32 AM 
        To: 
        Cc: PHP DB 
        Subject: Re: [PHP-DB] If syntax
        
        

        See below...
        
        Ron Piggott wrote:
        
        >Take a look at my if ( ) syntax line below.  I am wondering if I have 
it
        >wrong in same way.  What I am trying to achieve is if the alias the 
user
        >enters is already found in the database I want the words "Alias 
already in
        >use" to be shown on the screen; otherwise "Unique alias" to be shown 
on the
        >screen.
        >
        >PRESENTLY alias already in use is what comes up all the time.
        >
        >Ron
        >
        >
        >mysql_connect(localhost,$username,$password);
        >@mysql_select_db($database) or die( "Unable to select database");
        >$query="SELECT * FROM tablename WHERE alias LIKE '$alias%'";
        >
        >if (mysql_query($query))
        >
        >{
        >
        >echo "Alias already in use";
        >
        >} else {
        >
        >echo "Unique alias";
        >
        >mysql_close();
        >
        >}
        >
        > 
        >
        Whether or not there are any matches, you will always have a database
        query - hence mysql_query($query) will always produce something
        
        Instead you need to see if there are any  matches to your variable.
        
        Also, "SELECT * FROM [some_table] is tremendously inefficient when you
        only need to count results. You are basically calling up every result in
        your entire table just to see if a single column entry matches a 
variable.
        
        I would suggest something like..
        
        mysql_connect(localhost,$username,$password);
        @mysql_select_db($database) or die( "Unable to select database");
        $query="SELECT alias FROM tablename WHERE alias LIKE '$alias%' LIMIT 1";
        
        $result=(mysql_query($query))
        
         if (mysql_num_rows($result)==1)
        
        {
        
        echo "Alias already in use";
        
        } else {
        
        echo "Unique alias";
        
        mysql_close();
        
        }
        Good luck,
        
        Jeffrey
        
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