diff --git a/src/libmdb/data.c b/src/libmdb/data.c
index 432c82f..569e386 100644
--- a/src/libmdb/data.c
+++ b/src/libmdb/data.c
@@ -192,6 +192,9 @@ int mdb_fetch_row(MdbTableDef *table)
 MdbHandle *mdb = table->entry->mdb;
 int rows;
 
+	if (table->num_rows==0)
+		return 0;
+
 	/* initialize */
 	if (!table->cur_pg_num) {
 		table->cur_pg_num=1;
diff --git a/src/util/mdb-array.c b/src/util/mdb-array.c
index 4fdefa7..82fde0a 100644
--- a/src/util/mdb-array.c
+++ b/src/util/mdb-array.c
@@ -53,7 +53,8 @@ int started;
  for  (i = 0; i < mdb->num_catalog; i++) 
    {
      entry = g_array_index (mdb->catalog, MdbCatalogEntry, i);
-     if  (!strcmp (entry.object_name, argv [2])) 
+     if  (entry.object_type == MDB_TABLE &&
+		!strcmp (entry.object_name, argv [2])) 
        {
 	 table = mdb_read_table (&entry);
 	 mdb_read_columns (table);
diff --git a/src/util/mdb-export.c b/src/util/mdb-export.c
index 0473ba0..afd963b 100644
--- a/src/util/mdb-export.c
+++ b/src/util/mdb-export.c
@@ -48,7 +48,8 @@ char quote_text = 1;
 
 	for (i=0;i<mdb->num_catalog;i++) {
 		entry = g_array_index(mdb->catalog,MdbCatalogEntry,i);
-		if (!strcmp(entry.object_name,argv[2])) {
+		if (entry.object_type == MDB_TABLE &&
+			!strcmp(entry.object_name,argv[2])) {
 			table = mdb_read_table(&entry);
 			mdb_read_columns(table);
 			mdb_rewind_table(table);
diff --git a/src/util/prdata.c b/src/util/prdata.c
index 7bce7d4..baecec4 100644
--- a/src/util/prdata.c
+++ b/src/util/prdata.c
@@ -43,7 +43,8 @@ GList *l;
 
 	for (i=0;i<mdb->num_catalog;i++) {
 		entry = g_array_index(mdb->catalog,MdbCatalogEntry,i);
-		if (!strcmp(entry.object_name,argv[2])) {
+		if (entry.object_type == MDB_TABLE &&
+			!strcmp(entry.object_name,argv[2])) {
 				table = mdb_read_table(&entry);
 				mdb_read_columns(table);
 				mdb_data_dump(table);