Method getTimeDimensionExpression

runtime/metricsview/ast.go:1282–1304

getTimeDimensionExpression returns the SQL expression and data type code for the time dimension specified in the TimeRange or the metrics view's time dimension. It looks up the time dimension definition in the metrics view or returns the escaped column name from the model.

(tr *TimeRange)

// getTimeDimensionExpression returns the SQL expression and data type code for the time dimension specified in the TimeRange or the metrics view's time dimension.
// It looks up the time dimension definition in the metrics view or returns the escaped column name from the model.
func (a *AST) getTimeDimensionExpression(tr *TimeRange) (string, runtimev1.Type_Code, error) {
	timeDim := a.MetricsView.TimeDimension
	if tr.TimeDimension != "" {
		timeDim = tr.TimeDimension
	}

	t, err := a.LookupDimension(timeDim, true)
	if err != nil {
		return "", runtimev1.Type_CODE_UNSPECIFIED, fmt.Errorf("time dimension %q not found: %w", timeDim, err)
	}

	expr, err := a.Dialect.MetricsViewDimensionExpression(t)
	if err != nil {
		return "", runtimev1.Type_CODE_UNSPECIFIED, fmt.Errorf("failed to compile time dimension %q expression: %w", t.Name, err)
	}

	var typeCode runtimev1.Type_Code
	if t.DataType != nil {
		typeCode = t.DataType.Code
	}

	return expr, typeCode, nil
}

// checkNameForComputedField checks that the name for a computed field does not collide with an existing dimension or measure name.
// (This is necessary because even if the other name is not used in the query, it might be referenced by a derived measure.)