Where is the error in my sql code - php

Question

$fname = addslashes($fname);
$lname = addslashes($lname);
$dob = addslashes($dob);
$email = $_POST['email'];
$sql =
"INSERT INTO subscriber
(fname, lname, dob)
VALUES
('".$fname."', '".$lname."', '".$dob."')
WHERE email='".$email."'";
$register = mysql_query($sql) or die("insertion error");
I am getting error in sql query "insertion error". Query is inserting data into DB after removing WHERE statement. What is the error.

Answer 1

You can't use where in an insert statement. You might be thinking of an update instead?
$sql = "update subscriber set fname='".$fname."', lname = '".$lname."', dob = '".$dob."' WHERE email='".$email."'";
If your email is a unique value, you can also combine an insert with an update like this:
insert into
subscriber (fname, lname, dob, email)
values ('".$fname."', '".$lname."', '".$dob."', '".$email."')
on duplicate key update set fname='".$fname."', lname='".$lname."', dob='".$dob."'
This second syntax will insert a row if there isn't one with a matching email (again, this has to be set to a unique constraint on the table) and if there is one there already, it will update the data to the values you passed it.

Answer 2

Basically INSERT statement cannot have where. The only time INSERT statement can have where is when using INSERT INTO...SELECT is used.
The only syntax for select statement are
INSERT INTO TableName VALUES (val1, val2, ..., colN)
and
INSERT INTO TableName (col1, col2) VALUES (val1, val2)
The other one is the
INSERT INTO tableName (col1, col2)
SELECT col1, col2
FROM tableX
WHERE ....
basically what it does is all the records that were selected will be inserted on another table (can be the same table also).
One more thing, Use PDO or MYSQLI
Example of using PDO extension:
<?php
$dbh = new PDO('mysql:host=localhost;dbname=test', $user, $pass);
$stmt = $dbh->prepare("INSERT INTO REGISTRY (name, value) VALUES (?, ?)");
$stmt->bindParam(1, $name);
$stmt->bindParam(2, $value);
// insert one row
$name = 'one';
$value = 1;
$stmt->execute();
?>
this will allow you to insert records with single quotes.

Answer 3

Oops !!!! You cannot use a WHERE clause with INSERT statement ..
If you are targeting a particular row then please use UPDATE
$sql = "Update subscriber set fname = '".$fname."' , lname = '".$lname."' , dob = '".$dob."'
WHERE email='".$email."'";
$register = mysql_query($sql) or die("insertion error");