Exact error : SQLSTATE[42P07]: Duplicate table: 7 ERROR: relation "date_formats_formats_key" already exists
Seems to be caused by the use of "BINARY" (invalid in Postgre) in :
<?php
db_change_field('date_formats', 'format', 'format', array(
'description'=> 'The date format string.',
'type'=> 'varchar',
'length'=> 100,
'not null'=> TRUE,
'binary'=> TRUE,
), array('unique keys'=> array('formats'=> array('format', 'type'))));
?>Same issue as : #1768672: PostgreSQL/SQLite issue - BINARY syntax invalid