PHP mysql SELECT QUERY或一个

Question

mysql_query("SELECT * FROM foo WHERE id ='$foo' OR id = '$foo2");

This doesn't work.

Basically, I want to be able to select it where the id is one variable's value OR another one's.

Thanks.

EDIT: The ID column is numerical.

Answer 1

I think you forgot the last ' character

mysql_query("SELECT * FROM foo WHERE id ='$foo' OR id = '$foo2'");

but because the id column is numerical, you should use:

mysql_query("SELECT * FROM foo WHERE id = $foo OR id = $foo2");

Answer 2

As others have said and you confirmed, the problem is that you are using string literals to compare to a numeric column. To have it work, the query should look like

mysql_query("SELECT * FROM foo WHERE id =$foo OR id = $foo2");

However, this solution has very very bad code smell!

First off, this is why IN exists: to be able to write

mysql_query("SELECT * FROM foo WHERE id IN ($foo, $foo2)");

And second, are you injecting unescaped strings into your query? If you are, your code is vulnerable to sql injection ! Escape and quote your variables to be safe, like this (in the general case):

$query = sprintf("SELECT * FROM foo WHERE id IN ('%s', '%s')",
                 mysql_real_escape_string($foo),
                 mysql_real_escape_string($foo2));
mysql_query($query);

or alternatively like this, since in this specific scenario you know we 're talking about integer values:

$query = sprintf("SELECT * FROM foo WHERE id IN (%s, %s)",
                 intval($foo), intval($foo2));
mysql_query($query);

Footnote: I am aware that when using sprintf like this, one could also handle integer values by just using %d instead if %s as the format specifier. However, I believe that proving you are correctly escaping variables should be possible by just looking at one place (the parameter list) instead of multiple places (did I use intval on the variable? or maybe I did not, but I 'm using %d in the format string so I 'm still OK?). It may sound counter-intuitive, but it's more robust in the face of modifications.

Answer 3

Try this:

mysql_query(sprintf("SELECT * FROM foo WHERE id = %s OR id = %s", $foo, $foo2));

I recommend you use mysql_error() for get mysql errors(if exists).

mysql_query( .. ) or die('Erro:'.mysql_error());

the mysql_error returns the last error occurred in mysql.