如何在SELECT子句中使用多个WHERE表达式？ [关闭]

I have the following bit of code:

$query  = "SELECT * FROM jos_vm_product_details WHERE global_variant_id = '$global_variant_id'";
$result = mysql_query($query);


while($row = mysql_fetch_array($result)) {
$row['name'];
}

Is it possible to select the $row['name'] only where something is matched:

Select $row['name'] WHERE id = $id

Any help would be appreciated

I don't fully understand your question, but you can limit that in the query to begin with:

$query  = "SELECT * FROM jos_vm_product_details WHERE global_variant_id = '$global_variant_id' AND id = '$id'";
//-------------------------------------------------------------------------------------------^^^^^^^^^^^^^^^^
$result = mysql_query($query);

Otherwise if you need to limit it in the fetch loop, use something like:

while($row = mysql_fetch_array($result)) {
  if ($row['id'] == $id) {
    echo $row['name'];
  }
}

But this is better handled in the query's WHERE clause as in my first example.

You should change your SQL statement and append

AND id = '$id'

or, if you prefer, you can add a conditional statement within the while loop to skip to the next row if the id doesn't match (not recommended)

if ($row['id'] != $id) continue

http://dev.mysql.com/doc/refman/5.5/en/select.html

$query  = "SELECT name FROM jos_vm_product_details WHERE global_variant_id = '$global_variant_id'"

For the health of your application: never ever "filter" output in your application layer, your DB was designed to do all this stuff in the fastest and simplest way.

Do what Michael and Borodin said!