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42 lines
1.1 KiB
Plaintext
42 lines
1.1 KiB
Plaintext
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Dictionary for integers
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=======================
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The motivation for this example dictionary is to control the indexing of
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integers (signed and unsigned), and, consequently, to minimize the number of
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unique words which greatly affect the performance of searching.
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* Configuration
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The dictionary accepts two options:
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- The MAXLEN parameter specifies the maximum length (number of digits)
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allowed in an integer word. The default value is 6.
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- The REJECTLONG parameter specifies if an overlength integer should be
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truncated or ignored. If REJECTLONG=FALSE (default), the dictionary returns
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the first MAXLEN digits of the integer. If REJECTLONG=TRUE, the
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dictionary treats an overlength integer as a stop word, so that it will
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not be indexed.
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* Usage
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1. Compile and install
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2. Load dictionary
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psql mydb < dict_int.sql
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3. Test it
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mydb# select ts_lexize('intdict', '12345678');
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ts_lexize
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-----------
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{123456}
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4. Change its options as you wish
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mydb# ALTER TEXT SEARCH DICTIONARY intdict (MAXLEN = 4, REJECTLONG = true);
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ALTER TEXT SEARCH DICTIONARY
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That's all.
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