diff --git a/pkg/vpcagent/ovn/cmp.go b/pkg/vpcagent/ovn/cmp.go
new file mode 100644
index 0000000000..a84320d4d5
--- /dev/null
+++ b/pkg/vpcagent/ovn/cmp.go
@@ -0,0 +1,29 @@
+package ovn
+
+import (
+	"yunion.io/x/onecloud/pkg/vpcagent/ovnutil"
+)
+
+// cmp scans the database for irows.  For those present, mark them with ocver.
+// If all rows are found, return true to indicate this.  Otherwise return as
+// 2nd value the args to destroy these found records
+func cmp(db *ovnutil.OVNNorthbound, ocver string, irows ...ovnutil.IRow) (bool, []string) {
+	irowsFound := make([]ovnutil.IRow, 0, len(irows))
+
+	for _, irow := range irows {
+		irowFound := db.FindOneMatchNonZeros(irow)
+		if irowFound != nil {
+			irowsFound = append(irowsFound, irowFound)
+		}
+	}
+	// mark them anyway even if not all found, to avoid the destroy
+	// call at sweep stage
+	for _, irowFound := range irowsFound {
+		irowFound.OvnSetExternalIds(externalKeyOcVersion, ocver)
+	}
+	if len(irowsFound) == len(irows) {
+		return true, nil
+	}
+	args := ovnutil.OvnNbctlArgsDestroy(irowsFound)
+	return false, args
+}