Stop OGG
==========================
stop REPLICAT <replicat_name>
stop EXTRACT <extract_name>
stop MANAGER
Start OGG
==========================
start MANAGER
start EXTRACT <extract_name>
start REPLICAT <replicat_name>
Check status
==========================
info MANAGER detail
info EXTRACT <extract_name>
info REPLICAT <replicat_name>
View report file
==========================
view report EXTRACT <extract_name>
view report REPLICAT <replicat_name>
View/edit parameters
==========================
view/edit param EXTRACT <extract_name>
view/edit param REPLICAT <replicat_name>
==========================
Basic Concepts
--------------------------------------------
==========================
stop REPLICAT <replicat_name>
stop EXTRACT <extract_name>
stop MANAGER
Start OGG
==========================
start MANAGER
start EXTRACT <extract_name>
start REPLICAT <replicat_name>
Check status
==========================
info MANAGER detail
info EXTRACT <extract_name>
info REPLICAT <replicat_name>
View report file
==========================
view report EXTRACT <extract_name>
view report REPLICAT <replicat_name>
View/edit parameters
==========================
view/edit param EXTRACT <extract_name>
view/edit param REPLICAT <replicat_name>
==========================
Basic Concepts
--------------------------------------------
Manager
The Manager
process must be running on both the source as well as target systems before the
Extract or Replicat process can be started and performs a number of functions
including monitoring and starting other GoldenGate processes, managing the
trail files and also reporting.
Extract
The Extract
process runs on the source system and is the data caoture mechanism of
GoldenGate. It can be configured both for initial loading of the source data as
well as to synchronize the changed data on the source with the target. This can
be configued to also propagate any DDL changes on those databases where DDL
change support is available.
Replicat
The Replicat
process runs on the target system and reads transactional data changes as well
as DDL changes and replicates then to the target database. Like the Extract
process, the Replicat process can also be configured for Initial Load as well
as Change Synchronization.
Collector
The Collector is a
background process which runs on the target system and is started automatically
by the Manager (Dynamic Collector) or it can be configured to stsrt manually
(Static Collector). It receives extracted data changes that are sent via TCP/IP
and writes then to the trail files from where they are processed by the
Replicat process.
Trails
Trails are series
of files that GoldenGate temporarily stores on disks and these files are
written to and read from by the Extract and Replicat processes as the case may
be. Depending on the configuration chosen, these trail files can exist on the
source as well as on the target systems. If it exists on the local system, it
will be known an Extract Trail or as an Remote Trail if it exists on the target
system.
Data Pumps
Data Pumps are
secondary extract mechanisms which exist in the source configuration. This is
optional component and if Data Pump is not used then Extract sends data via
TCP/IP to the remote trail on the target. When Data Pump is configured, the the
Primary Extract process will write to the Local Trail and then this trail is
read by the Data Pump and data is sent over the network to Remote Trails on the
target system.
In the absence of
Data Pump, the data that the Extract process extracts resides in memory alone
and there is no storage of this data anywhere on the source system. In case of
network of target failures, there could be cases where the primary extract
process can abort or abend. Data Pump can also be useful in those cases where
we are doing complex filtering and transformation of data as well as when we
are consolidating data from many sources to a central target.
Data
source
When processing
transactional data changes, the Extract process can obtain data directly from
the database transaction logs (Oracle, DB2, SQL Server, MySQL etc) or from a
GoldenGate Vendor Access Module (VAM) where the database vendor (for example
Teradata) will provide the required components that will be used by Extract to
extract the data changes.
Groups
To differentiate
between the number of different Extract and Replicat groups which can
potentially co-exist on a system, we can define processing groups. For
instance, if we want to replicate different sets of data in parallel, we can
create two Replicat groups.
A processing group
consisits of a process which could be either a Extract or Replicat process, a
corresponding parameter file, checkpoint file or checkpoint table (for
Replicat) and other files which could be associated with the process.