provider/aws: Fixes issue 886 in DB Parameter group

builtin/providers/aws/resource_aws_db_parameter_group.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 	"log"
+	"strings"
 	"time"
 
 	"github.com/hashicorp/terraform/helper/hashcode"
@@ -220,7 +221,8 @@ func resourceAwsDbParameterHash(v interface{}) int {
 	var buf bytes.Buffer
 	m := v.(map[string]interface{})
 	buf.WriteString(fmt.Sprintf("%s-", m["name"].(string)))
-	buf.WriteString(fmt.Sprintf("%s-", m["value"].(string)))
+	// Store the value as a lower case string, to match how we store them in flattenParameters
+	buf.WriteString(fmt.Sprintf("%s-", strings.ToLower(m["value"].(string))))
 
 	return hashcode.String(buf.String())
 }