Description:
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For some queries, pg_field_type() returns the wrong field type. It seems to happen when you do a "SELECT *" and there are more than one table in the FROM-clause, with common columns eliminated.

I tested with postgresql 7.4 and postgresql 8.1, with the same result.

Reproduce code:
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<?php

$params = "host=localhost dbname=testdb user=testuser password=123456";
pg_pconnect($params);

pg_query("begin");
pg_query("CREATE TABLE test1(a integer)");
pg_query("CREATE TABLE test2(a integer, c varchar)");
pg_query("INSERT INTO test1 VALUES (1)");
pg_query("INSERT INTO test2 VALUES (1,'aa')");

$res = pg_query("SELECT * FROM test1 INNER JOIN test2 ON test1.a=test2.a");
$row = pg_fetch_assoc($res);

$col_i=0;
foreach ($row as $field_name => $dummy) {
  var_dump($field_name);
  $type = pg_field_type($res, $col_i++);
  var_dump($type);
  if ($field_name == "c") {
    assert($type != "int4");
  }
}

pg_query("rollback");

?>


Expected result:
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The type of column "c" should be "varchar"

Actual result:
--------------
The type of column "c" is "int4"