change comment

src/backend/gpopt/gpdbwrappers.cpp

@@ -2510,10 +2510,11 @@ static bool mdcache_invalidation_counter_registered = false;
 static int64 mdcache_invalidation_counter = 0;
 static int64 last_mdcache_invalidation_counter = 0;
 
-// if we have cached a relation without an index, because that index cannot
-// be used in the current snapshot (for more info see src/backend/access/heap/README.HOT),
-// we save TransactionXmin. If TransactionXmin changes later, the cache will
-// be reset and the relation will be reloaded with that index.
+// If we have cached a relation without an index, because that index cannot
+// be used in the current snapshot (for more info see
+// src/backend/access/heap/README.HOT), we save TransactionXmin. If
+// TransactionXmin changes later, the cache will be reset and the relation will
+// be reloaded with that index.
 static TransactionId mdcache_transaction_xmin = InvalidTransactionId;
 
 static void

src/include/gpopt/gpdbwrappers.h

@@ -687,14 +687,14 @@ gpos::ULONG CountLeafPartTables(Oid oidRelation);
 bool MDCacheNeedsReset(void);
 
 // Check that the index is usable in the current snapshot and if not, save the
-// xmin of the current snapshot. returns true if the index is not usable and
+// xmin of the current snapshot. Returns true if the index is not usable and
 // should be skipped.
 bool MDCacheSetTransientState(Relation index_rel);
 
 // reset TransactionXmin value that we saved
 void MDCacheResetTransientState(void);
 
-// check if TransactionXmin value that we saved are valid
+// returns true if cache is in transient state
 bool MDCacheInTransientState(void);
 
 // returns true if a query cancel is requested in GPDB