Description:
------------
Quoting table names and other identifiers is needed because they are 
case-sensitive in PostgreSQL.  As Marco pointed out reserved words 
also need to be quoted.

See section 4.1.1. Identifiers and Key Words
http://www.postgresql.org/docs/8.1/static/sql-syntax.html#SQL-SYNTAX-IDENTIFIERS

I'm not sure why sniper@php.net marked bug #28020 as bodus 3 years 
ago.

Reproduce code:
---------------
$Conn = pg_connect( "dbname=db" );

pg_query( $Conn, "insert into \"caseTest\" (foo) values (2)" ); // works
//pg_query( $Conn, "insert into   caseTest   (foo) values (2)" ); // fails correctly


echo pg_insert( $Conn, 'caseTest', array( 'foo' => 1 ), PGSQL_DML_STRING );
// INSERT INTO caseTest (foo) VALUES (1);

if (pg_insert( $Conn, 'caseTest', array( 'foo' => 1 ) ))
        echo 'success';
else
        echo 'failure';


Expected result:
----------------
 INSERT INTO caseTest (foo) VALUES (1);success

db=# select * from "caseTest";
 foo
-----
   2
   1
(2 rows)

Actual result:
--------------
 INSERT INTO caseTest (foo) VALUES (1);failure

db=# select * from "caseTest";
 foo
-----
   2
(1 row)