示例#1
0
// ScanIndexData scans the index handles and values in a limited number, according to the index information.
// It returns data and the next startVals until it doesn't have data, then returns data is nil and
// the next startVals is the values which can't get data. If startVals = nil and limit = -1,
// it returns the index data of the whole.
func ScanIndexData(txn kv.Transaction, kvIndex kv.Index, startVals []interface{}, limit int64) (
	[]*RecordData, []interface{}, error) {
	it, _, err := kvIndex.Seek(txn, startVals)
	if err != nil {
		return nil, nil, errors.Trace(err)
	}
	defer it.Close()

	var idxRows []*RecordData
	var curVals []interface{}
	for limit != 0 {
		val, h, err1 := it.Next()
		if terror.ErrorEqual(err1, io.EOF) {
			return idxRows, nextIndexVals(curVals), nil
		} else if err1 != nil {
			return nil, nil, errors.Trace(err1)
		}
		idxRows = append(idxRows, &RecordData{Handle: h, Values: val})
		limit--
		curVals = val
	}

	nextVals, _, err := it.Next()
	if terror.ErrorEqual(err, io.EOF) {
		return idxRows, nextIndexVals(curVals), nil
	} else if err != nil {
		return nil, nil, errors.Trace(err)
	}

	return idxRows, nextVals, nil
}
示例#2
0
// GetIndexRecordsCount returns the total number of the index records from startVals.
// If startVals = nil, returns the total number of the index records.
func GetIndexRecordsCount(txn kv.Transaction, kvIndex kv.Index, startVals []interface{}) (int64, error) {
	it, _, err := kvIndex.Seek(txn, startVals)
	if err != nil {
		return 0, errors.Trace(err)
	}
	defer it.Close()

	var cnt int64
	for {
		_, _, err := it.Next()
		if terror.ErrorEqual(err, io.EOF) {
			break
		} else if err != nil {
			return 0, errors.Trace(err)
		}
		cnt++
	}

	return cnt, nil
}