Method modify

src/dsql/StmtNodes.cpp:7064–7274

Execute a MODIFY statement.

// Execute a MODIFY statement.
const StmtNode* ModifyNode::modify(thread_db* tdbb, Request* request, WhichTrigger whichTrig) const
{
	jrd_tra* transaction = request->req_transaction;
	impure_state* impure = request->getImpure<impure_state>(impureOffset);

	record_param* orgRpb = &request->req_rpb[orgStream];
	jrd_rel* relation = orgRpb->rpb_relation;

	record_param* newRpb = &request->req_rpb[newStream];

	switch (request->req_operation)
	{
		case Request::req_evaluate:
			if (!(marks & MARK_AVOID_COUNTERS))
				request->req_records_affected.bumpModified(false);

			if (impure->sta_state == 0 && forNode && forNode->isWriteLockMode(request))
				request->req_operation = Request::req_return;
				// fall thru
			else
				break;

		case Request::req_return:
			if (impure->sta_state == 1)
			{
				impure->sta_state = 0;
				Record* orgRecord = orgRpb->rpb_record;
				const Record* newRecord = newRpb->rpb_record;
				orgRecord->copyDataFrom(newRecord, true);
				request->req_operation = Request::req_evaluate;
				return statement;
			}

			if (impure->sta_state == 0)
			{
				if (forNode && forNode->isWriteLockMode(request))
				{
					forceWriteLock(tdbb, orgRpb, transaction);
					return parentStmt;
				}

				// CVC: This call made here to clear the record in each NULL field and
				// varchar field whose tail may contain garbage.
				cleanupRpb(tdbb, newRpb);

				SavepointChangeMarker scMarker(transaction);

				// Prepare to undo changes by PRE-triggers if record is locked by another
				// transaction and update should be skipped.
				const bool skipLocked = orgRpb->rpb_stream_flags & RPB_s_skipLocked;
				CondSavepointAndMarker spPreTriggers(tdbb, transaction,
					skipLocked && !(transaction->tra_flags & TRA_system) && relation->rel_pre_modify);

				preModifyEraseTriggers(tdbb, &relation->rel_pre_modify, whichTrig, orgRpb, newRpb,
					TRIGGER_UPDATE);

				if (validations.hasData())
					validateExpressions(tdbb, validations);