Hologres:Function release notes

Version

Function type

Function

Category

Description

Execution engine

References

2.1.0

Funnel analysis functions

• range_funnel

• range_funnel_time

• range_funnel_level

New function

Hologres supports the range_funnel, range_funnel_time, and range_funnel_level functions.

• range_tunnel: Calculates grouping statistics and aggregates the calculation results of a time window.

• range_funnel_time: Decodes the event time in the result returned by the range_funnel function.

• range_funnel_level: Decodes the event level in the result returned by the range_funnel function.

HQE

Funnel and retention functions

2.1.0

Bit-sliced Index (BSI) functions

• BSI constructor function

• BSI expansion function

• BSI query function

• BSI aggregate and analytic function

New function

Hologres supports BSI functions to improve user profile analysis capabilities.

PQE

BSI functions (beta)

2.1.0

Supported MySQL functions

if

New function

Hologres supports the IF function.

HQE

IF

2.1.0

Array functions

• array[]

• array_append

Performance improvement

Hologres Query Engine (HQE) supports the array[] function that is used to obtain an array subscript and the array_append function that is used to append elements to an array.

HQE

Array functions

2.1.0

String functions

regexp_split_to_table

Performance improvement

HQE supports the regexp_split_to_table function that is used to split strings.

HQE

String functions

2.1.0

Set returning functions

generate_series

Performance improvement

HQE supports the generate_series function that is used to generate a sequence. The data types can be INT, BIGINT, or NUMERIC.

HQE

Set returning functions

Version

Function type

Function

Category

Description

Execution engine

References

2.0.31

Date and time functions

• dateadd

• datediff

• last_day

New function

Hologres supports the dateadd, datediff, and last_day functions.

HQE

Date and time functions

2.0.24

JSONB functions

try_cast_to_jsonb

New function

Hologres supports try_cast_to_jsonb function.

HQE

JSON and JSONB data types

2.0.8

Geographic information analysis functions

• ST_Distance_Sphere_S2

• ST_DWithin_S2

New function

Hologres supports the ST_Distance_Sphere_S2 function that is used to calculate the spherical distance and the ST_DWithin_S2 function that is used to check the distance relationship.

HQE

PostGIS for geographic information analysis

2.0.1

Supported ClickHouse functions

hg_sip_hash_64(text)

New function

The ClickHouse built-in function sipHash64 is added.

HQE

Supported ClickHouse functions

2.0.1

Data type conversion functions

• text::timestamp

• cast(text as timestamp)

• timestamp::text

• cast(timestamp as text)

Performance improvement

HQE supports conversion between the TEXT and TIMESTAMP data types.

HQE

Optimize query performance on Hologres internal tables

2.0.1

String functions

• left

• right

Performance improvement

HQE supports the string truncation functions left(string text, n int) and right(string text, n int).

HQE

String functions

Version

Function type

Function

Category

Description

Execution engine

References

1.3.39

Date and time functions

• extract

• date_part

• date_trunc

Performance improvement

HQE supports the following datetime truncation functions:

• extract

• date_part

• date_trunc

HQE

Datetime truncation functions

1.3.39

Roaring bitmap functions

rb_build

Performance improvement

The rb_build function allows you to use columns of the ARRAY type as input.

HQE

Roaring bitmap functions

1.3.37

Array operators

ARRAY && ARRAY

Performance improvement

The && operator allows you to use columns of the ARRAY type as input.

HQE

Array functions

1.3.36

Supported ClickHouse functions

• toString

• toInt64

• toInt32

• toDate

• toFloat64

New function

Some ClickHouse type conversion functions are supported.

HQE

ClickHouse functions compatible with Hologres

1.3.36

Aggregate functions

• MAX_BY

• MIN_BY

New function

The MAX_BY and MIN_BY functions are supported.

HQE

MAX_BY and MIN_BY

1.3.19

Array functions

• array_max

• array_min

• array_contains

• array_except

• array_distinct

• array_union

New function

Some array functions are supported.

HQE

Array functions

1.3.18

Array functions

array_sort

Performance improvement

The array_sort function supports more types of arrays.

HQE

Array functions

1.3.16

Roaring bitmap operators

• |

• <<

• >>

• -

New function

The roaring bitmap operators are supported in specific scenarios.

HQE

Roaring bitmap functions

1.3.16

Roaring bitmap functions

• rb_index

• rb_fill

• rb_clear

• rb_range

• rb_range_cardinality

New function

Some roaring bitmap functions are supported.

HQE

Roaring bitmap functions

1.3.12

JSON functions

is_valid_json

New function

The is_valid_json function is supported to validate JSON strings.

HQE

JSON and JSONB data types

1.3.1

Aggregate functions

UNIQ

New function

The UNIQ function is supported for precise deduplication.

HQE

UNIQ

1.3.1

• String functions

• Array functions

• array_agg

• string_agg

Performance improvement

Filter conditions are supported in expressions.

HQE

• String functions

• Array functions

1.3.1

String functions

• row_to_json

• row()

New function

Some string functions are supported.

HQE

String functions

1.3.1

PostGIS spatial functions

• Geometry Constructors

• Geometry Accessors

• Geometry Editors

• Spatial Reference System

• Geometry Input

• Geometry Output

• Spatial Relationships

• Measurement

• Overlay

• Geometry Processing

• Bounding Box

• Linear Referencing

Performance improvement

HQE supports most spatial functions and supports PostGIS at the production level.

HQE

PostGIS for geographic information analysis

1.3.1

Supported Oracle functions

Other functions such as date functions and string functions

New function

The orafce extension is introduced to support Oracle functions.

HQE

Supported Oracle functions