Method addDateTime

src/dsql/ExprNodes.cpp:2668–2727

Vector out to one of the actual datetime addition routines.

// Vector out to one of the actual datetime addition routines.
dsc* ArithmeticNode::addDateTime(thread_db* tdbb, const dsc* desc, impure_value* value) const
{
	BYTE dtype;					// Which addition routine to use?

	fb_assert(nodFlags & FLAG_DATE);

	// Value is the LHS of the operand.  desc is the RHS

	if (blrOp == blr_add)
		dtype = DSC_add_result[value->vlu_desc.dsc_dtype][desc->dsc_dtype];
	else
	{
		fb_assert(blrOp == blr_subtract);
		dtype = DSC_sub_result[value->vlu_desc.dsc_dtype][desc->dsc_dtype];

		/* Is this a <date type> - <date type> construct?
		   chose the proper routine to do the subtract from the
		   LHS of expression
		   Thus:   <TIME> - <TIMESTAMP> uses TIME arithmetic
		   <DATE> - <TIMESTAMP> uses DATE arithmetic
		   <TIMESTAMP> - <DATE> uses TIMESTAMP arithmetic */
		if (DTYPE_IS_NUMERIC(dtype))
			dtype = value->vlu_desc.dsc_dtype;

		// Handle historical <timestamp> = <string> - <value> case
		if (!DTYPE_IS_DATE(dtype) &&
			(DTYPE_IS_TEXT(value->vlu_desc.dsc_dtype) || DTYPE_IS_TEXT(desc->dsc_dtype)))
		{
			dtype = dtype_timestamp;
		}
	}

	switch (dtype)
	{
		case dtype_sql_time:
		case dtype_sql_time_tz:
			return addSqlTime(tdbb, desc, value);

		case dtype_sql_date:
			return addSqlDate(desc, value);

		case DTYPE_CANNOT:
			ERR_post(Arg::Gds(isc_expression_eval_err) << Arg::Gds(isc_invalid_type_datetime_op));
			break;

		case dtype_ex_time_tz:
		case dtype_ex_timestamp_tz:
			fb_assert(false);
			ERRD_post(Arg::Gds(isc_expression_eval_err));

		case dtype_timestamp:
		case dtype_timestamp_tz:
		default:
			// This needs to handle a dtype_sql_date + dtype_sql_time
			// For historical reasons prior to V6 - handle any types for timestamp arithmetic
			return addTimeStamp(tdbb, desc, value);
	}