Riak TS Release Notes
Released January 14, 2016.
This release builds on Riak TS 1.0.0 to enable further analysis of time series data with aggregates and arithmetic functionality.
New Features
Aggregations
In Riak TS 1.0.0 you could run aWHERE
clause that returned a particular row set of time series data. In 1.1.0 you can apply a function (such as COUNT
) in the SELECT
clause that operates on those responses in aggregate.
For instance,
SELECT fun(X) FROM tablename WHERE
Where fun
is one of:
SUM
COUNT
AVG
/MEAN
MIN
MAX
STDDEV
And where is (X) is either a column name, or a multi-column expression avg(temperature/pressure).
Arithmetic
Riak TS now also supports arithmetic operations in the SELECT
list. The arithmetic operations available in this release are: Numeric Literals, Addition, Subtraction, Multiplication, Division, and Negation.
- +
- -
- /
- *
- (
- )
For example,
SELECT 555, 1.1, 1e1, 1.123e-2 from GeoCheckin
WHERE time > 1452252523182 AND time < 1452252543182 AND myfamily = 'family1' AND myseries = 'series1'
Important: Arithmetic operations and aggregate functions cannot be mixed in a single value expression.
Dynamic Schema Discovery
You can now query a table definition with the DESCRIBE
table query which returns the table’s rows and columns.
For example:
DESCRIBE GeoCheckin
Returns (Rows and Columns):
Column | Type | Is Null | Partition Key | Local Key
--------------------------------------------------------
myfamily | varchar | false | 1 | 1
myseries | varchar | false | 2 | 2
time | timestamp | false | 3 | 3
weather | varchar | false | <null> | <null>
temperature | double | false | <null> | <null>
Create Tables via Clients
You can create tables using CREATE TABLE
. Simply execute your CREATE TABLE
command in a query, and it will be created.
CREATE TABLE GeoCheckin
(
myfamily varchar not null,
myseries varchar not null,
time timestamp not null,
weather varchar not null,
temperature double,
PRIMARY KEY (
(myfamily, myseries, quantum(time, 15, 'm')),
myfamily, myseries, time
)
)
A successful table creation will return nothing, and an exception response will be returned if the attempt was unsuccessful.
Compatibility
Riak TS is compatible with the following operating systems:
- RHEL/CentOS 6
- RHEL/CentOS 7
- Ubuntu 12.04 LTS
- Ubuntu 14.04 LTS
- Debian 7 (development only)
- OSX 10.8+ (development only)
Known Issues
- AAE must be turned off.
- Riak Search is not supported.
- Multi-Datacenter Replication is not supported.
- Arithmetic operations and aggregates cannot currently be combined.