[tracker] rasqal: Fix rasqal_query_add_prefix

[Jürg Billeter <juergbi src gnome org>]

commit db706cea9e01b0cebc4334dd562133b54ac8abb6
Author: Jürg Billeter <j bitron ch>
Date:   Thu Mar 12 17:53:22 2009 +0100

    rasqal: Fix rasqal_query_add_prefix
    
    Do not undeclare first different prefix.
---
 src/rasqal/rasqal_query.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/src/rasqal/rasqal_query.c b/src/rasqal/rasqal_query.c
index b4f00c2..1635685 100644
--- a/src/rasqal/rasqal_query.c
+++ b/src/rasqal/rasqal_query.c
@@ -963,7 +963,7 @@ rasqal_query_add_prefix(rasqal_query* query, rasqal_prefix* prefix)
     for(i = 0; i< raptor_sequence_size(query->prefixes); i++) {
       rasqal_prefix* p;
       p = (rasqal_prefix*)raptor_sequence_get_at(query->prefixes, i);
-      if(strcmp((const char*)p->prefix, (const char*)prefix->prefix)) {
+      if(!strcmp((const char*)p->prefix, (const char*)prefix->prefix)) {
         rasqal_query_undeclare_prefix(query, p);
         break;
       }