Flux data model

Warning! This page documents an earlier version of Flux, which is no longer actively developed. Flux v0.24 is the most recent stable version of Flux.

Note: This document is a living document and may not represent the current implementation of Flux. Any section that is not currently implemented is commented with a [IMPL#XXX] where XXX is an issue number tracking discussion and progress towards implementation.

Flux employs a basic data model built from basic data types. The data model consists of tables, records, columns and streams.


A record is a tuple of named values and is represented using an object type.


A column has a label and a data type. The available data types for a column are:

Data type Description
bool A boolean value, true or false.
uint An unsigned 64-bit integer.
int A signed 64-bit integer.
float An IEEE-754 64-bit floating-point number.
string A sequence of unicode characters.
bytes A sequence of byte values.
time A nanosecond precision instant in time.
duration A nanosecond precision duration of time.


A table is set of records with a common set of columns and a group key.

The group key is a list of columns. A table’s group key denotes which subset of the entire dataset is assigned to the table. All records within a table will have the same values for each column that is part of the group key. These common values are referred to as the “group key value” and can be represented as a set of key value pairs.

A tables schema consists of its group key and its columns’ labels and types.

Stream of tables

A stream represents a potentially unbounded set of tables. A stream is grouped into individual tables using their respective group keys. Tables within a stream each have a unique group key value.

Missing values

A record may be missing a value for a specific column. Missing values are represented with a special null value. The null value can be of any data type.

To be implemented: IMPL#300 Design how nulls behave