=?iso-8859-1?B?ZGrpIGRq6Q==?= <gerald2545@xxxxxxxxxxx> writes: > I get the error : ERROR: duplicate key violates unique constraint > "unique_barcode128" > But the string returned by text2code128('AB28662097') and > text2code128('AB28662098') are different!!!, i.e., respectively ÌABÇ<b4ÅÃÎ > and ÌABÇ<b4ÆÊÎ. What locale are you running the server in? It's possible that these strings are equal according to the locale-specific strcoll() behavior. In particular, if you are using a locale that expects UTF8, it's pretty common for strcoll to go nuts when faced with non-UTF8-legal strings. You might be better off using bytea instead of varchar. regards, tom lane