How does {} affect a MySQL Query in PHP? [duplicate]
What is the difference between the following 2 queries?
mysql_query("UPDATE table SET name = '$name'");
mysql_query("UPDATE table SET name = '{$name}'");
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}
.
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 $user['name']
it does. So there is nothing different between the two queries you have posted in your question.
This query can be used if you want to pass a single variable:
mysql_query("UPDATE table SET name = '$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.
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