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926bbab448
remove transactions use create or replace function make formatting consistent set search patch on first line Add documentation on modifying *.sql to set the search patch, and mention that major upgrades should still run the installation scripts. Some of these issues were spotted by Tom today. |
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| expected | ||
| sql | ||
| dict_int.c | ||
| dict_int.sql.in | ||
| Makefile | ||
| README.dict_int | ||
| uninstall_dict_int.sql | ||
Dictionary for integers
=======================
The motivation for this example dictionary is to control the indexing of
integers (signed and unsigned), and, consequently, to minimize the number of
unique words which greatly affect the performance of searching.
* Configuration
The dictionary accepts two options:
- The MAXLEN parameter specifies the maximum length (number of digits)
allowed in an integer word. The default value is 6.
- The REJECTLONG parameter specifies if an overlength integer should be
truncated or ignored. If REJECTLONG=FALSE (default), the dictionary returns
the first MAXLEN digits of the integer. If REJECTLONG=TRUE, the
dictionary treats an overlength integer as a stop word, so that it will
not be indexed.
* Usage
1. Compile and install
2. Load dictionary
psql mydb < dict_int.sql
3. Test it
mydb# select ts_lexize('intdict', '12345678');
ts_lexize
-----------
{123456}
4. Change its options as you wish
mydb# ALTER TEXT SEARCH DICTIONARY intdict (MAXLEN = 4, REJECTLONG = true);
ALTER TEXT SEARCH DICTIONARY
That's all.