NAME

       table_dispatcher - PgQ consumer that is used to write source records into partitoned
       table.

SYNOPSIS

       table_dispatcher.py [switches] config.ini

DESCRIPTION

       table_dispatcher is PgQ consumer that reads url encoded records from source queue and
       writes them into partitioned tables according to configuration file. Used to partiton
       data. For example change log’s that need to kept online only shortly can be written to
       daily tables and then dropped as they become irrelevant. Also allows to select which
       columns have to be written into target database Creates target tables according to
       configuration file as needed.

QUICK-START

       Basic table_dispatcher setup and usage can be summarized by the following steps:

        1. PgQ must be installed in source database. See pgqadm man page for details. Target
           database must have pgq_ext schema installed.

        2. edit a table_dispatcher configuration file, say table_dispatcher_sample.ini

        3. create source queue

               $ pgqadm.py ticker.ini create <queue>

        4. launch table dispatcher in daemon mode

               $ table_dispatcher.py table_dispatcher_sample.ini -d

        5. start producing events

CONFIG

   Common configuration parameters
       job_name
           Name for particulat job the script does. Script will log under this name to
           logdb/logserver. The name is also used as default for PgQ consumer name. It should be
           unique.

       pidfile
           Location for pid file. If not given, script is disallowed to daemonize.

       logfile
           Location for log file.

       loop_delay
           If continuisly running process, how long to sleep after each work loop, in seconds.
           Default: 1.

       connection_lifetime
           Close and reconnect older database connections.

       log_count
           Number of log files to keep. Default: 3

       log_size
           Max size for one log file. File is rotated if max size is reached. Default: 10485760
           (10M)

       use_skylog
           If set, search for [./skylog.ini, ~/.skylog.ini, /etc/skylog.ini]. If found then the
           file is used as config file for Pythons logging module. It allows setting up fully
           customizable logging setup.

   Common PgQ consumer parameters
       pgq_queue_name
           Queue name to attach to. No default.

       pgq_consumer_id
           Consumers ID to use when registering. Default: %(job_name)s

   table_dispatcher parameters
       src_db
           Source database.

       dst_db
           Target database.

       dest_table
           Where to put data. when partitioning, will be used as base name

       part_field
           date field with will be used for partitioning.

       part_template
           SQL code used to create partition tables. Various magic replacements are done there:

       _PKEY
           comma separated list of primery key columns.

       _PARENT
           schema-qualified parent table name.

       _DEST_TABLE
           schema-qualified partition table.

       _SCHEMA_TABLE
           same as DEST_TABLE but dots replaced with "_", to allow use as index names.

   Example config
           [table_dispatcher]
           job_name          = table_dispatcher_source_table_targetdb

           src_db            = dbname=sourcedb
           dst_db            = dbname=targetdb

           pgq_queue_name    = sourceq

           logfile           = log/%(job_name)s.log
           pidfile           = pid/%(job_name)s.pid

           # where to put data.  when partitioning, will be used as base name
           dest_table        = orders

           # names of the fields that must be read from source records
           fields            = id, order_date, customer_name

           # date field with will be used for partitioning
           part_field        = order_date

           # template used for creating partition tables
           part_template     =
                create table _DEST_TABLE () inherits (orders);
                alter table only _DEST_TABLE add constraint _DEST_TABLE_pkey primary key (id);
                grant select on _DEST_TABLE to group reporting;

COMMAND LINE SWITCHES

       Following switches are common to all skytools.DBScript-based Python programs.

       -h, --help
           show help message and exit

       -q, --quiet
           make program silent

       -v, --verbose
           make program more verbose

       -d, --daemon
           make program go background

       Following switches are used to control already running process. The pidfile is read from
       config then signal is sent to process id specified there.

       -r, --reload
           reload config (send SIGHUP)

       -s, --stop
           stop program safely (send SIGINT)

       -k, --kill
           kill program immidiately (send SIGTERM)

LOGUTRIGA EVENT FORMAT

       PgQ trigger function pgq.logutriga() sends table change event into queue in following
       format:

       ev_type

           (op || ":" || pkey_fields). Where op is either "I", "U" or "D", corresponging to
           insert, update or delete. And pkey_fields is comma-separated list of primary key
           fields for table. Operation type is always present but pkey_fields list can be empty,
           if table has no primary keys. Example: I:col1,col2

       ev_data
           Urlencoded record of data. It uses db-specific urlecoding where existence of = is
           meaningful - missing = means NULL, present = means literal value. Example:
           id=3&name=str&nullvalue&emptyvalue=

       ev_extra1
           Fully qualified table name.

                                            03/13/2012                        TABLE_DISPATCHER(1)