...

TD_APPROX_MOST_FREQUENT

Signature

 TD_APPROX_MOST_FREQUENT(long num_buckets, long/varchar values, long capacity)

Example

SELECT TD_APPROX_MOST_FREQUENT(3, values, 10);

Description

This function picks the frequent distinct items from the collection of values. This selection is approximate. The top `num_buckets` elements are obtained `values`. It returns a map whose keys are elements and values are estimated frequencies in the collection.

Unlike a normal histogram, it selects the frequent values online to significantly save memory resources. The error rate is bounded by the capacity parameter controlling the size of the internal data structure.

TD_TIME_RANGE

For convenience, we recommend using TD_INTERVAL instead of TD_TIME_RANGE.

...

SELECT ... WHERE TD_TIME_RANGE(time, '2013-01-01 PDT')                 # OK
SELECT ... WHERE TD_TIME_RANGE(time, '2013-01-01', '2013-01-02','PDT') # OK
SELECT ... WHERE TD_TIME_RANGE(time, NULL, '2013-01-01', 'PDT')        # OK
SELECT ... WHERE TD_TIME_RANGE(time, '2013-01-01', NULL, 'PDT')        # OK
SELECT ... WHERE TD_TIME_RANGE(time, '2013-01-01', 'PDT')              # NG

Description

This UDF returns true if the unix_timestamp is equal to or later than the start_time and older than the end_time (start_time <= time && time < end_time). If end_time is omitted or NULL, the UDF assumes it’s infinite. If start_time is NULL, the UDF assumes it’s 0.

...

TD_INTERVAL() is a companion function to TD_TIME_RANGE(). Both are especially useful in WHERE clauses, to make sure that your queries take advantage of time-based partitioning. TD_INTERVAL is used to compute relative time ranges that would otherwise require complex date manipulation. (TD_TIME_RANGE is used for absolute time ranges.)

This UDF returns true if time value is within the interval which is represented by interval_string (state time <= time < end time).

...

If the formats of the time or duration strings are invalid, the UDF returns NULL.

TD_TIME_FORMAT

For convenience, we recommend using TD_TIME_STRING instead of TD_TIME_FORMAT.

...

TD_TIME_FORMAT converts a UNIX timestamp to a string with the specified format (see the Supported time formats in TD_TIME_FORMAT UDF page for available formats). For example, ‘yyyy-MM-dd HH:mm:ss z’ converts 1325376000 to ‘2012-01-01 00:00:00 UTC’. If no timezone is specified, the UDF uses UTC.

...

If the format string has ! as the suffix, it truncates the date time string at the specified unit.

If there is no !, the return value should be the same as:

...

This UDF returns the result of parsing a user agent string. The user agent is parsed on the basis of rules. Where options are:

Example

The example shows the result of parsing user agent from access log.

...

SELECT TD_CURRENCY_CONV('2015-01-01', 'USD', 'JPY', 1.0)

TD_IP_TO_COUNTRY_CODE

An example of different results is as follows:

Signature

string TD_IP_TO_COUNTRY_CODE(string ip)

...

SELECT groupkey, SORTED_GROUP_CONCAT(column, '.', time)
FROM table
GROUP BY groupkey

Notes for Geometry types

ST_Point

Signature

point ST_Point(double, double)

...

RESULT: Park Area Hope Fountain 4000 Hot Springs 5156

ST_Intersection

Signature

Geometry ST_Intersection(Geometry, Geometry) 

...