The document discusses MySQL fulltext search. It covers setting up a MyISAM table with a FULLTEXT INDEX for column content, different fulltext search modes like natural language and boolean, options for Chinese fulltext search like using tokenizers or MySQL plugins, and examples comparing LIKE queries to MATCH AGAINST fulltext searches on tables of different sizes.

1. MySQL FullText Search

2. 條件
engine : MyISAM
column : CHAR, VARCHAR, TEXT
config : ft_min_word_len

3. 建立資料庫
CREATE TABLE t
(
content CHAR(255),
FULLTEXT INDEX (content) WITH PARSER my_parser
) ENGINE=MyISAM;
ALTER TABLE t ADD FULLTEXT INDEX (content) WITH
PARSER my_parser;

4. 檢索模式
Natural Language (Stopwords)
BOOLEAN (+ - ~ > <)

5. 中文檢索
(MySQL 預設不支援中文檢索)
tokenizer + text encode (base64, unicode,
urlencode)
mysql plug-in (mecab(詞庫)、bigram(N-gram))

6. 測試
SELECT * FROM t WHERE content LIKE '%台北%';
4000筆 : 0.060 s
12000筆 : 0.15 s
SELECT * FROM t WHERE MATCH(content) AGAINST('+"
台北"' IN BOOLEAN MODE);
4000筆 : 0.016 s
12000筆 : 0.04 s

8. Reference
MySQL :: MySQL 5.0 Reference Manual :: 12.9 Full-Text Search Functions
http://dev.mysql.com/doc/refman/5.0/en/fulltext-search.html
y-ken/mysqlftppc-mecab
https://github.com/y-ken/mysqlftppc-mecab
使用 N-gram 演算來支援 MySQL 中文全文檢索
https://github.com/y-ken/mysqlftppc-bigram/blob/master/INSTALL
FullText search of MySQL supported for SQLAlchemy
https://github.com/mengzhuo/sqlalchemy-fulltext-search