Using Sphinx to Index MySQL Table

Question

I've tried googling this but I'm not sure if my terminology is wrong or I have the wrong idea on how to use Sphinx.

I need some help with creating and searching a index of a table from a database using something like sphinx. I'm running Ubuntu 14.04 LTS.

My sphinx configuration file looks like this:

source db1
{
        sql_host                = localhost
        sql_user                = user1
        sql_pass                = pswd123
        sql_db                  = db1
        sql_port                = 3306

        type      = mysql
        sql_query = SELECT * FROM MetaData;
}

index myidx
{
    source            = mureinome
    path              = /var/lib/sphinxsearch/data/myidx
    docinfo           = extern

    # Added after suggestion from Mihai
    min_stemming_len  = 1
    min_word_len      = 1
    dict              = keywords
}
indexer
{
        mem_limit    = 1000M
        write_buffer = 50M
}
searchd
{
        listen                  = 9312
        listen                  = 9306:mysql41
        pid_file                = /var/run/sphinxsearch/searchd.pid
        binlog_path             = /var/lib/sphinxsearch/data
}

To index the table I run:

root@M4:/var/lib/sphinxsearch# indexer myidx --rotate
Sphinx 2.2.10-id64-release (2c212e0)
Copyright (c) 2001-2015, Andrew Aksyonoff
Copyright (c) 2008-2015, Sphinx Technologies Inc (http://sphinxsearch.com)

using config file '/etc/sphinxsearch/sphinx.conf'...
indexing index 'myidx'...
WARNING: Attribute count is 0: switching to none docinfo
collected 1 docs, 0.0 MB
sorted 0.0 Mhits, 100.0% done
total 1 docs, 459 bytes
total 0.005 sec, 80286 bytes/sec, 174.91 docs/sec
total 3 reads, 0.000 sec, 0.6 kb/call avg, 0.0 msec/call avg
total 9 writes, 0.000 sec, 0.6 kb/call avg, 0.0 msec/call avg
rotating indices: successfully sent SIGHUP to searchd (pid=2444).

But when I try to search the index I get an empty result:

SELECT * FROM myidx WHERE MATCH('FC') LIMIT 0,5;
Empty set (0.00 sec)

In MySQL One of the columns in the table looks like this:

mysql> select SampleName from MetaData;
+-----------------+
| SampleName      |
+-----------------+
| FCPG1048_S1S2S3 |
+-----------------+
1 row in set (0.00 sec)

Am I indexing the table wrong or am I searching the index wrong? Any help is greatly appreciated.

Answer 1

To enable part word matching need to use min_prefix_len or min_infix_len

http://sphinxsearch.com/docs/current.html#conf-min-prefix-len

Once done that can use a * in the query. Or use expand_keywords to effectivly do it automatically.