What is a forward index?
A forward index, also known as an attribute index or profile index, is an index that stores the value of a specific field for each document. It is used for filtering, aggregations, sorting, and scoring. The term "forward" refers to the direct mapping from a document to its field value (doc --> field value).
Supported data types
The engine supports the following basic data types for fields in a forward index:
|
Type |
Description |
Single value |
Multi-value |
|
INT8 |
An 8-bit signed integer. |
id=-27 |
id=-27^]26^]33 |
|
UINT8 |
An 8-bit unsigned integer. |
id=56 |
id=27^]222^]32 |
|
INT16 |
A 16-bit signed integer. |
id=-2724 |
id=-1217^]236 |
|
UINT16 |
A 16-bit unsigned integer. |
id=65531 |
id=65531^]22236^]0^]1 |
|
INTEGER |
A 32-bit signed integer. |
id=-655312 |
id=-2714442^]2344126^]33441 |
|
UINT32 |
A 32-bit unsigned integer. |
id=65537 |
id=4011341512^]26^]33 |
|
INT64 |
A 64-bit signed integer. |
id=-551533527 |
id=-2416664447^]236^]133 |
|
UINT64 |
A 64-bit unsigned integer. |
id=23545114533527 |
id=12416664447^]121436^]2 |
|
FLOAT |
A 32-bit single-precision floating-point number. |
id=3.14 |
id=3.25^]3.50^]3.75 |
|
DOUBLE |
A 64-bit double-precision floating-point number. |
id=3.1415926 |
id=-3.1415926^]26.1444^]55.1441 |
|
STRING |
A sequence of characters. |
id=abc |
id=abc^]def^]dgg^]dd |