if (row->old == row->new) {
continue;
} else if (!row->new) {
- struct json *op = json_object_create();
- json_object_put_string(op, "op", "delete");
- json_object_put_string(op, "table", class->name);
- json_object_put(op, "where", where_uuid_equals(&row->uuid));
- json_array_add(operations, op);
- any_updates = true;
+ if (class->is_root) {
+ struct json *op = json_object_create();
+ json_object_put_string(op, "op", "delete");
+ json_object_put_string(op, "table", class->name);
+ json_object_put(op, "where", where_uuid_equals(&row->uuid));
+ json_array_add(operations, op);
+ any_updates = true;
+ } else {
+ /* Let ovsdb-server decide whether to really delete it. */
+ }
} else {
struct json *row_json;
struct json *op;
&class->columns[idx];
if (row->old
- ? !ovsdb_datum_equals(&row->old[idx], &row->new[idx],
- &column->type)
- : !ovsdb_datum_is_default(&row->new[idx],
+ || !ovsdb_datum_is_default(&row->new[idx],
&column->type)) {
json_object_put(row_json, column->name,
substitute_uuids(
assert(row->old == NULL ||
row->table->modes[column_idx] & OVSDB_IDL_MONITOR);
+ /* If this is a write-only column and the datum being written is the same
+ * as the one already there, just skip the update entirely. This is worth
+ * optimizing because we have a lot of columns that get periodically
+ * refreshed into the database but don't actually change that often.
+ *
+ * We don't do this for read/write columns because that would break
+ * atomicity of transactions--some other client might have written a
+ * different value in that column since we read it. */
+ if (row->table->modes[column_idx] == OVSDB_IDL_MONITOR
+ && ovsdb_datum_equals(ovsdb_idl_read(row, column),
+ datum, &column->type)) {
+ ovsdb_datum_destroy(datum, &column->type);
+ return;
+ }
+
if (hmap_node_is_null(&row->txn_node)) {
hmap_insert(&row->table->idl->txn->txn_rows, &row->txn_node,
uuid_hash(&row->uuid));