Nothing works when i try to delete a record

minds_gifts

I want to delete the author names from a table and with the code which I've written I am able to do that.But, in my table i also have author names who has'nt written any books.
Can i only get the list of author names who has'nt written any books.I've AUT_ID in my TBL_BOOKS.

would anybody help me how to re-write my code.

Many thanks

Ok, i've 2 tables TBL_AUTHORS and TBL_BOOKS.
I wanting to delete the author name from the TBL_AUTHORS.

<?
if (isset($delete)) {

// delete author name

$sql = "DELETE FROM TBL_AUTHORS WHERE AUT_ID=$id";
$result = mysql_query($sql);

}

// print the list of author names 

$result = mysql_query("SELECT * FROM TBL_AUTHORS ORDER BY AUT_NAME "); 

?>
<table width="75%" border="1" cellspacing="1">
<?PHP

   while ($myrow = mysql_fetch_array($result)) { 
?>
<tr>
<td><?PHP echo $myrow['AUT_NAME']; ?></td>
<td><a href="<?PHP echo $_SERVER['PHP_SELF']; ?>?id=<?PHP echo $myrow['AUT_ID']; ?>&delete=yes">
<img src="delete.gif" width="20" height="19" border="0"></a></td>
</tr>
<?PHP
    };
?>
</table>

cockney

should this line

<td><a href="<?PHP echo $_SERVER['PHP_SELF']; ?>?id=<?PHP echo $myrow['id']; ?>&delete=yes">

read

<td><a href="<?PHP echo $_SERVER['PHP_SELF']; ?>?id=<?PHP echo $myrow['AUT_ID']; ?>&delete=yes">

maybe

cockney

seems that you sussed it, & edited the thread !

minds_gifts

hi cockney,

yeah, I found the error by myself.do you have any idea how i can get the list of author names who has'nt written any books or in other words if somebody tries to delete the author name who has written books, he has to show a mesg something like that

Thank you

cockney

well not realy without knowing the structure of your db.

But it sounds like you want to make a second db query before you delete the author.

maybe query the books table with "SELECT COUNT (*) FROM book_table WHERE author='author' , or something like that.

Then if result[0] > 0 do something

ahundiak

Something like this should work:
http://www.mysql.com/doc/en/JOIN.html

* If there is no matching record for the right table in the ON or USING part in a LEFT JOIN, a row with all columns set to NULL is used for the right table. You can use this fact to find records in a table that have no counterpart in another table:

mysql> SELECT table1.* FROM table1
-> LEFT JOIN table2 ON table1.id=table2.id
-> WHERE table2.id IS NULL;

This example finds all rows in table1 with an id value that is not present in table2 (that is, all rows in table1 with no corresponding row in table2). This assumes that table2.id is declared NOT NULL, of course. See section 5.2.6 How MySQL Optimises LEFT JOIN and RIGHT JOIN.