[columnar] Delete / Update

* Created new metadata table `columnar.row_mask` that will indicate
  which rows can be skipped when reading columnar table.
* When doing delete bit information in row_mask for table / row number
  will be marked.
* Updates are combination of delete and insert
* columnar.create_table_row_mask function can be used to initialize row
  mask for columnar tables.

columnar/src/backend/columnar/columnar.c

@@ -44,6 +44,7 @@ int columnar_compression_level = 3;
 bool columnar_enable_parallel_execution = true;
 int columnar_min_parallel_processes = 8;
 bool columnar_enable_vectorization = true;
+bool columnar_enable_dml = true;
 
 static const struct config_enum_entry columnar_compression_options[] =
 {
@@ -154,6 +155,17 @@ columnar_init_gucs()
 							 NULL, 
 							 NULL, 
 							 NULL);
+
+	DefineCustomBoolVariable("columnar.enable_dml",
+							gettext_noop("Enables DML"),
+							NULL,
+							&columnar_enable_dml,
+							true,
+							PGC_USERSET,
+							GUC_NO_SHOW_ALL,
+							NULL, 
+							NULL, 
+							NULL);
 }
 
 

columnar/src/backend/columnar/columnar.control

@@ -1,4 +1,4 @@
 comment = 'Hydra Columnar extension'
-default_version = '11.1-4'
+default_version = '11.1-5'
 module_pathname = '$libdir/columnar'
 relocatable = false

columnar/src/backend/columnar/columnar_customscan.c

@@ -1851,14 +1851,22 @@ ColumnarAttrNeeded(ScanState *ss, List *customList)
 	{
 		Var *var = lfirst(lc);
 
-		if (var->varattno < 0)
+		/* 
+		 * We support following special variables with update / delete.
+		 */
+		if (var->varattno == SelfItemPointerAttributeNumber ||
+			var->varattno == TableOidAttributeNumber)
 		{
-			ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-							errmsg(
-								"UPDATE and CTID scans not supported for ColumnarScan")));
+			continue;
+		}
+		else if (var->varattno < SelfItemPointerAttributeNumber)
+		{
+			ereport(ERROR, 
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					 errmsg("MIN / MAX TransactionID or CommandID not supported for ColumnarScan")));
 		}
 
-		if (var->varattno == 0)
+		if (var->varattno == 0 )
 		{
 			elog(DEBUG1, "Need attribute: all");
 

columnar/src/backend/columnar/columnar_debug.c

@@ -36,8 +36,9 @@ PG_FUNCTION_INFO_V1(columnar_storage_info);
 
 
 /*
- * columnar_store_memory_stats returns a record of 3 values: size of
- * TopMemoryContext, TopTransactionContext, and Write State context.
+ * columnar_store_memory_stats returns a record of 4 values: size of
+ * TopMemoryContext, TopTransactionContext, , Write State context and
+ * Row Mask context.
  */
 Datum
 columnar_store_memory_stats(PG_FUNCTION_ARGS)
@@ -52,21 +53,26 @@ columnar_store_memory_stats(PG_FUNCTION_ARGS)
 					   INT8OID, -1, 0);
 	TupleDescInitEntry(tupleDescriptor, (AttrNumber) 3, "WriteStateContext",
 					   INT8OID, -1, 0);
+	TupleDescInitEntry(tupleDescriptor, (AttrNumber) 4, "RowMaskWriteStateContext",
+					   INT8OID, -1, 0);
 
 	tupleDescriptor = BlessTupleDesc(tupleDescriptor);
 
 	MemoryContextCounters transactionCounters = { 0 };
 	MemoryContextCounters topCounters = { 0 };
 	MemoryContextCounters writeStateCounters = { 0 };
+	MemoryContextCounters rowMaskCacheCounters = { 0 };
 	MemoryContextTotals(TopTransactionContext, &transactionCounters);
 	MemoryContextTotals(TopMemoryContext, &topCounters);
-	MemoryContextTotals(GetWriteContextForDebug(), &writeStateCounters);
+	MemoryContextTotals(GetColumnarWriteContextForDebug(), &writeStateCounters);
+	MemoryContextTotals(GetRowMaskWriteStateContextForDebug(), &rowMaskCacheCounters);
 
-	bool nulls[3] = { false };
-	Datum values[3] = {
+	bool nulls[4] = { false };
+	Datum values[4] = {
 		Int64GetDatum(topCounters.totalspace),
 		Int64GetDatum(transactionCounters.totalspace),
-		Int64GetDatum(writeStateCounters.totalspace)
+		Int64GetDatum(writeStateCounters.totalspace),
+		Int64GetDatum(rowMaskCacheCounters.totalspace)
 	};
 
 	HeapTuple tuple = heap_form_tuple(tupleDescriptor, values, nulls);