diff --git a/src/obidms.c b/src/obidms.c
index ab7c61a..de555a2 100755
--- a/src/obidms.c
+++ b/src/obidms.c
@@ -1496,7 +1496,7 @@ obiversion_t obi_import_column(const char* dms_path_1, const char* dms_path_2, c
 	memcpy(column_2->data, column_1->data, header_1->data_size);
 
 	// Copy the AVL files if there are some (overwriting the automatically created files)
-	if ((header_1->returned_data_type == OBI_STR) || (header_1->returned_data_type == OBI_SEQ) || (header_1->returned_data_type == OBI_QUAL))
+	if ((header_1->tuples) || ((header_1->returned_data_type == OBI_STR) || (header_1->returned_data_type == OBI_SEQ) || (header_1->returned_data_type == OBI_QUAL)))
 	{
 		avl_name_1 = (char*) malloc((strlen(header_1->indexer_name) + 1)  * sizeof(char));
 		if (avl_name_1 == NULL)
diff --git a/src/obidmscolumn.c b/src/obidmscolumn.c
index ff1fc73..ac6d1ba 100644
--- a/src/obidmscolumn.c
+++ b/src/obidmscolumn.c
@@ -1693,8 +1693,8 @@ int obi_close_column(OBIDMS_column_p column)
 		if (obi_dms_unlist_column(column->dms, column) < 0)
 			ret_val = -1;
 
-		// If the data type is OBI_STR, OBI_SEQ or OBI_QUAL, the associated indexer is closed
-		if (((column->header)->returned_data_type == OBI_STR) || ((column->header)->returned_data_type == OBI_SEQ) || ((column->header)->returned_data_type == OBI_QUAL))
+		// If it's a tuple column or the data type is OBI_STR, OBI_SEQ or OBI_QUAL, the associated indexer is closed
+		if (((column->header)->tuples) || (((column->header)->returned_data_type == OBI_STR) || ((column->header)->returned_data_type == OBI_SEQ) || ((column->header)->returned_data_type == OBI_QUAL)))
 			if (obi_close_indexer(column->indexer) < 0)
 				ret_val = -1;