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Development Tools Using PHP with MySQL Using Relationship Tables in MySQL Fetching in a While Loop

Posted by Evan Shellborn
Evan Shellborn
4,827 Points

SQL While loop help

This is the while loop randy uses in this video:

while ($row = $results->fetch(PDO::FETCH_ASSOC)) {
  $product["sizes"][] = $row["size"];
}

I don't understand why it fetches a new row every time. When you call the fetch command, shouldn't it give you the first row of the table? So then it should enter the while loop, and then when it loops through a second time, why does it give the second row of the table? Nothing changes in the fetch statement, so it seems like it should be an infinite loop.

Also, can you explain what the $row["size"] command does? I'm a bit unclear about where the "size" key comes from.

Thanks!!