diff --git a/tsl/src/compression/create.c b/tsl/src/compression/create.c
index 366a5aa7441..e9557506e10 100644
--- a/tsl/src/compression/create.c
+++ b/tsl/src/compression/create.c
@@ -808,7 +808,7 @@ validate_existing_constraints(Hypertable *ht, CompressColInfo *colinfo, Bitmapse
 		 * We are saving all checked indexes here even though only the unique
 		 * index is a problem at this point. It potentially avoids a second
 		 * check of an index that we have already checked. */
-		if (form->conindid)
+		if (OidIsValid(form->conindid))
 			*indexes = bms_add_member(*indexes, form->conindid);
 
 		/*