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RDS for PostgreSQL

Extensions

Chinese search (pg_jieba)

pg_jieba is a PostgreSQL extension for Chinese word segmentation full-text search.

Precautions

pg_jieba not only provides basic word segmentation functions but also offers the capability for custom word segmentation. To use the custom word segmentation feature, pg_jieba must be added to the shared_preload_libraries parameter. For detailed information on modifying parameters, please refer to Modifying parameters.

tip

It is recommended to make business plans and impact assessments in advance before modifying the parameters.

Create and delete extension

Create extension

tip

A super account is required to create the extension.

create extension pg_jieba;

Delete extension

drop extension pg_jieba;

Extension usage

Basic usage

postgres=# select * from to_tsquery('jiebacfg', '是拖拉机学院手扶拖拉机专业的。不用多久，我就会升职加薪，当上CEO，走上人生巅峰。');
to_tsquery
----------------------------------------------------------------------------------------------------------------------------------
'拖拉机' & '学院' & '手扶拖拉机' & '专业' & '不用' & '多久' & '会' & '升职' & '加薪' & '当上' & 'ceo' & '走上' & '人生' & '巅峰'
(1 row)

postgres=# select * from to_tsvector('jiebacfg', '是拖拉机学院手扶拖拉机专业的。不用多久，我就会升职加薪，当上CEO，走上人生巅峰。');
to_tsvector
--------------------------------------------------------------------------------------------------------------------------------------------
'ceo':18 '不用':8 '专业':5 '人生':21 '会':13 '加薪':15 '升职':14 '多久':9 '学院':3 '巅峰':22 '当上':17 '手扶拖拉机':4 '拖拉机':2 '走上':20
(1 row)

-- Token And Tag
postgres=# select * from ts_token_type('jieba');
tokid | alias | description
-------+-------+-----------------------------
1 | eng | letter
2 | nz | other proper noun
3 | n | noun
4 | m | numeral
5 | i | idiom
6 | l | temporary idiom
7 | d | adverb
8 | s | space
9 | t | time
10 | mq | numeral-classifier compound
11 | nr | person's name
12 | j | abbreviate
13 | a | adjective
14 | r | pronoun
15 | b | difference
16 | f | direction noun
17 | nrt | nrt
18 | v | verb
19 | z | z
20 | ns | location
21 | q | quantity
22 | vn | vn
23 | c | conjunction
24 | nt | organization
25 | u | auxiliary
26 | o | onomatopoeia
27 | zg | zg
28 | nrfg | nrfg
29 | df | df
30 | p | prepositional
31 | g | morpheme
32 | y | modal verbs
33 | ad | ad
34 | vg | vg
35 | ng | ng
36 | x | unknown
37 | ul | ul
38 | k | k
39 | ag | ag
40 | dg | dg
41 | rr | rr
42 | rg | rg
43 | an | an
44 | vq | vq
45 | e | exclamation
46 | uv | uv
47 | tg | tg
48 | mg | mg
49 | ud | ud
50 | vi | vi
51 | vd | vd
52 | uj | uj
53 | uz | uz
54 | h | h
55 | ug | ug
56 | rz | rz
(56 rows)

Advanced use - Customize word segmentation effect

After completing the prerequisites, the following parameters will take effect. These configuration options can help customize word segmentation effects to meet specific business needs.

pg_jieba.hmm_model -- HMM Model file.
pg_jieba.base_dict -- Base dictionary.
pg_jieba.user_dict -- csv list of specific user dictionary name(Exclude suffix .dict). All should located in dir tsearch_data.

Others

For more information, please refer to pg_jieba official documentation.

Last updated: 2026.01.13 18:44:18