checking if exist .... count error.

raschidt

I need chek if the title insert exist on the DB, before insert that item, then I use:

$checkcTitle = "select COUNT(*)  from comercials were cTitle=".$title."";
$result = mysql_query($checkcTitle);
         if (mysql_result($result,0) > 0){

		  //if (!$result){

	  echo "that Comercial Name (".$title.")is taken -go back and chose another one.";
	  echo $checkcTitle;
	 }else{

here the insert
}

But I got an error:
Warning: mysql_result(): supplied argument is not a valid MySQL result resource in /bdb3.php on line 78

the line 78 is:
if (mysql_result($result,0) > 0){

whiy I have this error.?
How to correct?

Thanks!
😉 😉

diego25

When you get those kinds of errors, it usually means that there's something wrong with your SQL.

Since $title is a string, you need quotes around it in the SQL statement:

$checkcTitle = "select COUNT(*) from comercials were cTitle='".$title."'";

Diego

Frederick

If you are looking for a specific title, you can not use count(*). This is for totals.

<?php

$sql = mysql_query("SELECT * FROM comercials WHERE title='$title' ",$db)
or die(mysql_error());
$row = mysql_fetch_array($sql);

$temp = "".$row["title"]."";

if ($temp == $title) {
echo "title is already taken";

} else {

$sql = mysql_query("INSERT INTO ........................

}
?>

diego25

COUNT() can be used. He's trying to see if the title already exists, so if the count is > 0, it means that the title already exists.

Diego

raschidt

Frederics's code work fine, but mine (count ) don't work.

My code all time give me error in:
if (mysql_result($result,0) > 0){

why?

I need configure something before?

😕 😕 😕

diego25

Did you read my first reply??

Diego

raschidt

Yah, Diego I did that but does not work!

Thanks.
I deside used the Fredericks code.😉

ahundiak

Here is something that might be easier.

Create a UNIQUE INDEX on cTitle. This prevents two records from having the same cTitle. Then just insert your record and test to see if the insertion worked or not.

This also eliminates the possibility of two people trying to insert the same title at the same time.

raschidt

Ahungetc. that's intersting.

Are you sayin>

If the insertion= error then
echo "sorry but the your cTitle are selected by other user, please select another one"

???

It works fine?

ahundiak

Yep.

Think about it. You should always error check anyways and this way you avoid the need to do checking before doing the insert.

By the way, mysql_errno will be set to 1062 if an insert fails because of a duplicate unique field.