diff --git a/test/execsql.sh b/test/execsql.sh
index 7209c82..e58fbf3 100755
--- a/test/execsql.sh
+++ b/test/execsql.sh
@@ -387,8 +387,8 @@ case $? in
 	2) ShowHelp; exit;;
 esac
 
-export ISC_USER=SYSDBA
-export ISC_PASSWORD=masterkey
+if [[ -z $ISC_USER ]]; then export ISC_USER=SYSDBA; fi
+if [[ -z $ISC_PASSWORD ]]; then export ISC_PASSWORD=masterkey; fi
 
 echo "$(date) Started"