Ejemplo n.º 1
0
// Return the number of dropped ticks from filtering. if the series
// had more than one alias, returns the min of all dropped ticks
func (self *LevelDbDatastore) sendBatch(query *parser.SelectQuery, series *protocol.Series, yield func(series *protocol.Series) error) (int, error) {
	dropped := int(math.MaxInt32)

	for _, alias := range query.GetTableAliases(*series.Name) {
		_alias := alias
		newSeries := &protocol.Series{Name: &_alias, Points: series.Points, Fields: series.Fields}

		lengthBeforeFiltering := len(newSeries.Points)
		var filteredResult *protocol.Series
		var err error
		if query.GetFromClause().Type == parser.FromClauseInnerJoin {
			filteredResult = newSeries
		} else {
			filteredResult, err = Filter(query, newSeries)
			if err != nil {
				return 0, err
			}
		}
		_dropped := lengthBeforeFiltering - len(filteredResult.Points)
		if _dropped < dropped {
			dropped = _dropped
		}
		if err := yield(filteredResult); err != nil {
			return 0, err
		}
	}

	return dropped, nil
}