sphinx Lost connection to MySQL server during query

Question

I'm tyring to convert plain indices to real time by running the following query

ATTACH INDEX comment TO RTINDEX comment_rt;

But when I run it in sphinxql it gives me the following error:

WARNING: sql_query_post[0]: error=Lost connection to MySQL server during query, 
query=ATTACH INDEX comment TO RTINDEX comment_rt

My sphinx configuration:

source base
{
    type = mysql
    sql_host = localhost
    sql_user = root
    sql_pass = NastyBalls123
    sql_db   = telefind
    sql_port = 3306 # optional, default is 9306

}

source comment : base
{
    sql_query = \
    SELECT id, content, thread_id, user_id, rank, level, \
    UNIX_TIMESTAMP(date_time_added) AS date_time FROM comment

    sql_attr_uint = id
    sql_attr_uint = thread_id
    sql_attr_uint = user_id
    sql_attr_uint = rank
    sql_attr_uint = level
    sql_attr_timestamp = date_time
}

index comment 
{
    source = comment
    charset_type = sbcs
    path = /usr/local/sphinx/data/non_rt/comment
    phrase_boundary_step = 0

    index_sp = 0
    stopword_step = 1
    dict = crc
}

index comment_rt
{
    type            = rt
    rt_mem_limit        = 32M

    path            = /usr/local/sphinx/data/comment_rt
    charset_type        = utf-8

    rt_field        = title
    rt_field        = content
    rt_attr_uint        = group_id
    rt_attr_timestamp = date_added
}

in the sphinx's documentation at this page it mentions that you should have the following settings prehand:

• Target RT index needs to be empty.
• Source disk index needs to have index_sp=0, boundary_step=0, stopword_step=1, dict=crc settings.
• Source disk index needs to have an empty index_zones setting.

Answer 1

The fields and attributes of your Disk index, does not match the definitions in the RT index.

They need to be identical.