1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
|
.. -*- rst -*-
.. groonga-command
.. database: functions_query_parallel_or
``query_parallel_or``
=====================
.. versionadded:: 11.0.1
Summary
-------
``query_parallel_or`` is similar to :doc:`query` but
``query_parallel_or`` processes query that has multiple ``OR``
conditions in parallel.
Syntax
------
``query_parallel_or`` requires two or more parameters -
``match_columns`` and ``query_string`` s.
The ``options`` parameter is optional.
::
query(match_columns, query_string0, query_string1, ..., query_stringN)
query(match_columns, query_string0, query_string1, ..., query_stringN, options)
You must specify at least one ``query_string``.
``options`` uses the following format. All of key-value pairs are
optional::
{
"expander": query_expander,
"default_mode": default_mode,
"default_operator": default_operator,
"flags": flags
}
Usage
-----
Here are a schema definition and sample data to show usage.
Sample schema:
.. groonga-command
.. include:: ../../example/reference/functions/query_parallel_or/usage_setup_schema.log
.. table_create Documents TABLE_NO_KEY
.. column_create Documents content COLUMN_SCALAR Text
.. table_create Terms TABLE_PAT_KEY ShortText --default_tokenizer TokenBigram --normalizer NormalizerAuto
.. column_create Terms documents_content_index COLUMN_INDEX|WITH_POSITION Documents content
.. table_create Users TABLE_NO_KEY
.. column_create Users name COLUMN_SCALAR ShortText
.. column_create Users memo COLUMN_SCALAR ShortText
.. table_create Lexicon TABLE_HASH_KEY ShortText \
.. --default_tokenizer 'TokenNgram("unify_alphabet", false)' \
.. --normalizer NormalizerNFKC130
.. column_create Lexicon users_name COLUMN_INDEX|WITH_POSITION Users name
.. column_create Lexicon users_memo COLUMN_INDEX|WITH_POSITION Users memo
Sample data:
.. groonga-command
.. include:: ../../example/reference/functions/query_parallel_or/usage_setup_data.log
.. load --table Users
.. [
.. {"name": "Alice", "memo": "Groonga user"},
.. {"name": "Alisa", "memo": "Mroonga user"},
.. {"name": "Bob", "memo": "Rroonga user"},
.. {"name": "Tom", "memo": "Nroonga user"},
.. {"name": "Tobby", "memo": "Groonga and Mroonga user. Mroonga is ..."}
.. ]
Here is an example to execute full text searches in parallel by
``query_parallel_or`` function:
.. groonga-command
.. include:: ../../example/reference/functions/query_parallel_or/usage_basic.log
.. select Users \
.. --output_columns name,memo,_score \
.. --filter 'query_parallel_or("name * 10 || memo", "alice", "Groonga")'
This ``select`` command needs to execute the following full text
searches:
* ``"alice"`` against ``name``
* ``"alice"`` against ``memo``
* ``"Groonga"`` against ``name``
* ``"Groonga"`` against ``memo``
And all result sets of them are needed to be combined by ``OR``.
``query`` function executes them in a sequential
order. ``query_parallel_or`` function executes them in
parallel. Result sets of both of them are same.
Parameters
----------
Required parameters
^^^^^^^^^^^^^^^^^^^
There are two required parameters, ``match_columns`` and
``query_string``.
.. _query-parallel-or-match-columns:
``match_columns``
"""""""""""""""""
Specifies the default target columns for full text search by
``query_string`` parameters. It is the same role as
:ref:`select-match-columns` parameter in ``select``.
Each pair of target column and query string is processed in
parallel. For example, ``query_parallel_or("C1 || C2 || C3", "Q1",
"Q2")`` has the following pairs:
* ``C1 @ "Q1"``
* ``C2 @ "Q1"``
* ``C3 @ "Q1"``
* ``C1 @ "Q2"``
* ``C2 @ "Q2"``
* ``C3 @ "Q2"``
Each pair is processed in parallel. Degree of parallelism is depends
on your system. The default max number of threads is ``N_CPU_THREADS /
3``.
``query_string``
""""""""""""""""
Specifies the search condition in
:doc:`/reference/grn_expr/query_syntax`. It is the same role as
``query`` parameter in ``select``.
See :ref:`select-match-columns` about ``query`` parameter in
``select``.
You can specify multiple ``query_string`` s to execute full text
searches in parallel. See also :ref:`query-parallel-or-match-columns`
how to parallelize.
Optional parameter
^^^^^^^^^^^^^^^^^^
There are some optional parameters.
``query_expander``
""""""""""""""""""
See :ref:`query-query-expander` for details.
``default_mode``
""""""""""""""""
See :ref:`query-default-mode` for details.
``default_operator``
""""""""""""""""""""
See :ref:`query-default-operator` for details.
``flags``
"""""""""
See :ref:`query-flags` for details.
Return value
------------
This function returns whether a record is matched or not as boolean.
This function is also worked as a selector. It means that this
function can be executable effectively.
See also
--------
* :doc:`/reference/commands/select`
* :doc:`query`
|
