statistics

type Column struct {
	ID  int64 // Column ID.
	NDV int64 // Number of distinct values.

	// Histogram elements.
	//
	// A bucket number is the number of items stored in all previous buckets and the current bucket.
	// bucket numbers are always in increasing order.
	//
	// A bucket value is the greatest item value stored in the bucket.
	//
	// Repeat is the number of repeats of the bucket value, it can be used to find popular values.
	//
	// We could have make a bucket struct contains number, value and repeat, but that would be harder to
	// serialize, so we store every bucket field in its own slice instead. those slices all have
	// the bucket count length.
	Numbers []int64
	Values  []types.Datum
	Repeats []int64
}

type ColumnPB struct {
	Id               *int64  `protobuf:"varint,1,opt,name=id" json:"id,omitempty"`
	Ndv              *int64  `protobuf:"varint,2,opt,name=ndv" json:"ndv,omitempty"`
	Numbers          []int64 `protobuf:"varint,3,rep,name=numbers" json:"numbers,omitempty"`
	Value            []byte  `protobuf:"bytes,4,opt,name=value" json:"value,omitempty"`
	Repeats          []int64 `protobuf:"varint,5,rep,name=repeats" json:"repeats,omitempty"`
	XXX_unrecognized []byte  `json:"-"`
}

type Table struct {
	TS      int64 // build timestamp.
	Columns []*Column
	Count   int64 // Total row count in a table.
	// contains filtered or unexported fields
}

type TablePB struct {
	Id               *int64      `protobuf:"varint,1,opt,name=id" json:"id,omitempty"`
	Ts               *int64      `protobuf:"varint,2,opt,name=ts" json:"ts,omitempty"`
	Count            *int64      `protobuf:"varint,3,opt,name=count" json:"count,omitempty"`
	Columns          []*ColumnPB `protobuf:"bytes,4,rep,name=columns" json:"columns,omitempty"`
	XXX_unrecognized []byte      `json:"-"`
}