How does {} affect a MySQL Query in PHP?

Question

What is the difference between the following 2 queries?

mysql_query(\"UPDATE table SET name = \'$name\'\");

mysql_query(\"UPDATE table SET name = \'{$name}\         


        

Answer 1

ON the SQL side, there is absolutely no difference : the two queries are exactly the same.
(you can check that by echo-ing them)

{$variable} is a more complete syntax of $variable, that allows one to use :

• "this is some {$variable}s"
• "{$object->data}"
• "{$array['data']}"
• "{$array['data']->obj->plop['test']}"

For more informations, you should read the Variable parsing / Complex (curly) syntax section of the manual (quoting a few bits) :

This isn't called complex because the syntax is complex, but because it allows for the use of complex expressions.

Any scalar variable, array element or object property with a string representation can be included via this syntax.
Simply write the expression the same way as it would appear outside the string, and then wrap it in { and }.

Answer 2

This query can be used if you want to pass a single variable:

mysql_query("UPDATE table SET name = '$name'");

This can be used if you are passing a value from an array's particular index.

mysql_query("UPDATE table SET name = '{$1}'",$name);

By the way your both queries were also correct in their means.

Answer 3

The curly braces "escape" the PHP variable and are not passed to MySQL. With a simple variable like $name it doesn't make a difference but with something like $user['name'] it does. So there is nothing different between the two queries you have posted in your question.