Case insensitivity in column and table names

We are in the process of converting some databases from MySQL to PostgreSQL
-- our code to access these databases is in PHP. Our convention for column
and table names is to use uppercase words.

e.g. select ID, USERNAME from USERS where ID=42;

(We find that this convention visually makes it easy to see the important
details of the query.)

In the PHP, we may have something like:

$result = mysql_query('select ID, USERNAME from USERS where ID=42');
$row = mysql_fetch_assoc($result);

$id = $row['ID'];
$username = $row['USERNAME'];

We have encountered a big problem when doing the same thing in Postgres, as
Postgres seems to lowercase all the column names. Since associative arrays
in PHP *are* case-sensitive, all of our existing code thus breaks with the
exact same tables.

Is there any way possible to get Postgres to preserve the case we give it
when we create our tables? I've done many searches, and can't seem to find
anything helpful. Surely others have encountered this problem in the past.

Thanks,

Patrick

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patrick gibson
http://patrickgibson.com/