Mysql full-text search matchagainst usage

Full-text retrieval is a FULLTEXT index in MySQL. FULLTEXT indexes are used for MyISAM tables. You can use ALTERTABLE or CREATEINDEX to create indexes in CHAR, VARCHAR, or TEXT columns at or after CREATETABLE.

Full-text retrieval is a FULLTEXT index in MySQL. FULLTEXT indexes are used in MyISAM tables. You can use alter table or create index to CREATE indexes in CHAR, VARCHAR, or TEXT columns at or after create table.

For large databases, it is very fast to load data to a TABLE without FULLTEXT indexes and then CREATE an INDEX using alter table (or create index. Loading data to a table with FULLTEXT indexes will be very slow.
1. Prerequisites for using Mysql full-text search fulltext
The table type must be MyISAM.
The field type for full-text search must be char, varchar, and text.

2. Create an advanced configuration for full-text search
Because the default configuration of Mysql is that the index word length is 4, to support Chinese words, first change this.
* Unix users need to modify my. cnf. Generally, this file is stored in/etc/my. cnf. If not found, find/-name 'my. cnf 'first'
Add the following content to the [mysqld] location:
Ft_min_word_len = 2
Other attributes include
Ft_wordlist_charset = gbk
Ft_wordlist_file =/home/soft/mysql/share/mysql/wordlist-gbk.txt.
Ft_stopword_file =/home/soft/mysql/share/mysql/stopwords-gbk.txt.
A little explanation:
Ft_wordlist_charset indicates the character set of the dictionary, which currently supports (UTF-8, gbk, gb2312, big5)
Ft_wordlist_file is a Word Table file. Each line contains one word and its word frequency (separated by several tabs or spaces, dedicated for elimination)
Ft_stopword_file indicates filtering out non-indexed word lists, one row.
The minimum length of the word ft_min_word_len is added to the index. The default value is 4. To support Chinese words, change to 2.

3. Create a full-text search
The FullText keyword is used to identify the field in the TABLE under construction. The existing TABLE uses alter table (or create index) to CREATE an INDEX.
CREATE fulltext INDEX index_name ON table_name (colum_name );

4. Use full-text search
Use the MATCH function IN the WHERE clause of the SELECT statement. the keywords of the index are identified by AGAINST. in boolean mode only supports the keyword. You do not need to care about the position or whether it is the starting position.
SELECT * FROM articles where match (tags) AGAINST ('travel 'in boolean mode );

5. For details, please visit the Mysql official website.

This is Mysql 5.1, but 4.x can also be used as a reference. Basically, Mysql 4.1 is used.

MySQL full-text index and Chinese Word Segmentation summary and general keyword search process

Mysql full-text search Chinese Word Segmentation

Support Chinese MySQL 5.1 + full-text search and Word Segmentation plug-in

By using the search engine, you will find that word segmentation only occurs when the entire word hits 0.
For details about word segmentation, refer to the baidu search test results:

· If you search for "Xu zuningning", the result is "Xu zu" + "Ning ". (If you search for a person's name, it may have a hundred dictionaries with the last name. The first word after the last name is automatically prefixed)
· Search "Xu prefers" and the result is "Xu prefers ". (It means "would rather" be owned by "Xu. Same as above. Because Xu is the surname .)
· Search "Xu zu prefers" and the result is "Xu zu" + "yes ". (Because "preferred" is the word, "Xu" only takes "Zu ".)
· Search for "Xu zening GAO" and the result is "Xu zening ". (Because "Ning Gao" is not a keyword, "Ning" is owned by the prefix. However, "high" may be omitted because it is a single word to improve the efficiency of word search .)