Migrating External Loader Sessions to Dual Load

Migrating External Loader Sessions to Dual
Load Sessions
© 2011 Informatica Corporation
Abstract
You can migrate PowerCenter sessions that load to a Teradata target with external loaders that load to Teradata DualActive systems. This article describes how to migrate PowerCenter sessions that load to a Teradata target with external
loaders to dual load sessions.
Supported Versions
¨ PowerCenter 8.6.1 - 9.1.0
¨ PowerExchange for Teradata Parallel Transporter API 8.6.1 - 9.1.0
Table of Contents
Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Converting External Loader Sessions to Dual Load Sessions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Teradata Dual Load Connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Creating a Teradata Dual Load Connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Mapping External Loader Properties to TPT API Properties. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Mapping TPump to Dual Load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Mapping Mload to Dual Load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Mapping FastLoad to Dual Load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Mapping FastExport to TPT API. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Limitations of Dual Load over External Loaders. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Converting an External Loader Session to a Dual Load Session. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Teradata PT API Target Properties. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Scenario: Migration from Single Loader Session to Dual Load Session. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Overview
PowerCenter supports the following external loaders when you load to Teradata targets:
¨ Multiload. Performs insert, update, delete, and upsert operations for large volume incremental loads.
¨ TPump. Performs insert, update, delete, and upsert operations for relatively low volume updates.
¨ Fastload. Performs insert operations for high volume initial loads, or for high volume truncate and reload operations.
The sessions with external loaders cannot load to Teradata Dual Active servers. If you migrate to Teradata Dual Active
server, convert your existing PowerCenter sessions that write to a Teradata target to dual load sessions.
PowerCenter Dual Load Option for Teradata is a solution based on PowerCenter and PowerExchange for Teradata Parallel
Transporter API that helps you to load data to Teradata Dual Active servers.
PowerCenter Dual Load Option for Teradata provides Teradata dual load connection that loads data to the Teradata Dual
Load server. If you want to migrate to Teradata Dual Active server and retain the existing sessions, replace Teradata
loaders with Teradata dual load connection in the session.
2
Converting External Loader Sessions to Dual Load Sessions
To convert an external loader session to a dual load session:
1.
Configure a Teradata Dual Load connection.
2.
Create a copy of the session that you want to convert.
3.
Create dual load connection object with the same properties used in the external loader configuration.
4.
Modify the target connection in the copied session to use the Teradata Dual Load connection.
5.
Configure the dual load session properties with the same properties used in the external loader configuration.
Teradata Dual Load Connection
You must provide a Teradata Dual Load connection to the target instance. A Teradata Dual Load connection loads data to
the Teradata Dual Active servers with Teradata PT API.
The following table describes the Teradata Dual Load connection properties:
3
Attribute
Description
Primary TDPID
Name of the primary Teradata server. Default is $$PrimaryServerTDPIDWF. When you run the
workflow, the workflow assigns the primary server name that you configure as the workflow variable.
Note: If you edit the default value, verify that you enter the same value as the
$$PrimaryServerTDPIDWF variable in the workflow.
Secondary TDPID
Name of the secondary Teradata server. Default is $$SecondaryServerTDPIDWF. When you run
the workflow, the workflow assigns the secondary server name that you configure as the workflow
variable.
Note: If you edit the default value, verify that you enter the same value as the
$$SecondaryServerTDPIDWF variable in the workflow.
Database Name
Name of the Teradata database.
If you do not enter a database name, Teradata PT API uses the default login database name.
Tenacity
Number of hours that Teradata PT API continues trying to log on when the maximum number of
operations runs on the Teradata database.
Must be a positive integer. Default is 4.
Max Sessions
Maximum number of sessions that Teradata PT API establishes with the Teradata database.
Must be a positive integer. Default is 4.
Min Sessions
Minimum number of Teradata PT API sessions required for the Teradata PT API job to continue.
Must be a positive integer between 1 and the Max Sessions value. Default is 1.
Sleep
Number of minutes that Teradata PT API pauses before it retries to log in when the maximum
number of operations runs on the Teradata database.
Must be a positive integer. Default is 6.
Data Encryption
Enables full security encryption of SQL requests, responses, and data.
Default is disabled.
Block Size
Maximum block size, in bytes, that Teradata PT API uses when it returns data to the PowerCenter
Integration Service.
Minimum is 256. Maximum is 64,330. Default is 64,000.
Attribute
Description
System Operator
Teradata PT API operator type:
- Load. Bulk loads data into an empty Teradata database table.
- Update. Performs update, insert, upsert, and delete operations against Teradata database
tables.
- Stream. Performs update, insert, upsert, and delete operations against Teradata database
tables in near real-time mode. Select Stream if you want to enable recovery for sessions that
load data to Teradata.
Default is Stream.
Note: Do not use the Export operator for dual load sessions. Dual load sessions are not designed to
read data from Teradata.
File Location
Location of the staging file. You must have access to create files and directories in this location.
Each dual load target must have a unique file location.
File location should not contain spaces. The session fails if the file location contain spaces.
Default is $$FileLocationWF. When you run the workflow, the PowerCenter Integration Service
assigns the the value of the $$FileLocationWF variable that you configure as the workflow variable.
To configure the connection for a second target, enter the name of the workflow variable that you
configured for the target file location.
Note: If you edit the default value, verify that you enter the same value as the file location variable
in the workflow.
File Name
Name of the staging file.
Default is $$FileNameWF. When you run the workflow, the PowerCenter Integration Service assigns
the the value of the $$FileNameWF variable that you configure as the workflow variable.
File name should not contain spaces. The session fails if the file location contain spaces.
To configure the connection for a second target enter the name of the workflow variable that you
configured for the target file name.
Note: If you edit the default value, verify that you enter the same value as the file name variable in
the workflow.
Creating a Teradata Dual Load Connection
1.
Click Connections > Relational in the Workflow Manager.
The Relational Connection Browser dialog box appears.
2.
Click New.
The Select Subtype dialog box appears.
3.
Select Teradata Dual Load Connection, and then click OK.
The Relational Connection Editor dialog box appears.
4.
4
Enter the following properties for the connection:
Property
Description
Name
Connection name used by the Workflow Manager. Connection name cannot contain spaces or other
special characters, except underscore (_).
User Name
Database user name with permissions to access the database.
To define the user name in the parameter file, enter the session parameter $ParamName as the user
name, and define the value in the session or workflow parameter file. The PowerCenter Integration
Service interprets user names that start with $Param as session parameters.
Property
Description
Use Parameter in
Password
Indicates the password for the database user name is a session parameter, $ParamName. If you
enable this option, define the password in the workflow or session parameter file, and encrypt using
the pmpasswd CRYPT_DATA option. Default is disabled.
Password
Password for the database user name.
Code Page
Code page associated with the database.
When you run the session that extracts data from a Teradata source or loads data to a Teradata
target, the code page of the Teradata PT API connection must be the same as the code page of the
Teradata source and the target.
5.
Enter the Teradata Dual Load connection attributes.
6.
Click OK.
Mapping External Loader Properties to TPT API Properties
When you migrate from external loaders to dual load, you must configure the session and connection properties to match
the external loader properties.
Mapping TPump to Dual Load
The following table describes the mapping of the TPump properties to the Dual Load session and connection properties:
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TPump Property
TPT API Property
Session/
Connection
Description
TDPID
TDPID
Connection
Host name of the Teradata database.
Database Name
Database Name
Connection
Working database name.
Error Limit
Error Limit
Session
Maximum number of rows that TPT API rejects before it
stops loading data to the database table.
Checkpoint
Commit Interval
Session
Number of rows transmitted to the Teradata database
between checkpoints.
Tenacity
Tenacity
Connection
Number of hours TPT API tries to log in to the required
sessions when the maximum number of load jobs are
already running on the Teradata database
Load Mode
n/a
Drop Error Tables
Drop Error Tables
External Loader
Executable
n/a
Mode to generate SQL commands: Insert, Delete,
Update, Upsert, or Data Driven.
Not applicable for TPT API since TPT API does not use
control file. To flag the rows for upsert, you can use the
session property Update Else Insert.
Session
Drops the error tables before beginning the next
session. The session fails if non-empty error tables
exist from a prior job.
Name and optional file path of the Teradata external
loader executable. If the external loader executable
TPump Property
TPT API Property
Session/
Connection
Description
directory is not in the system path, you must enter the
full path.
Not applicable for TPT API since TPT API transfers the
buffers without staging any data.
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Max Sessions
Max Sessions
Connection
Maximum number of TPT API sessions in a job. Max
Sessions must be between 1 and the total number of
access module processes (AMPs) on the system
Sleep
Sleep
Connection
Number of minutes that TPT API pauses before retrying
a login. TPump/TPT API tries until the login succeeds
or the number of hours specified in the Tenacity
attribute elapses
Packing Factor
Pack
Session
Number of rows that each session buffer holds. Packing
improves network and channel efficiency by reducing
the number of sends and receives between the target
flat file and the Teradata database.
Statement Rate
n/a
Serialize
Serialize
Robust
n/a
If you enable Robust, TPump begins at the last
checkpoint when you restart the session. TPump
reloads any data that was loaded after the checkpoint.
Not applicable for TPT API sessions. Robust is enabled
by default for CDC sources to support recovery.
No Monitor
n/a
Prevents TPump from checking for statement rate
changes from, or update status information for, the
TPump monitor application.
Not applicable for TPT API sessions since user cannot
control statement rate.
Is Staged
n/a
Loads data to a flat file staging area before loading to
the database. Otherwise, the data is loaded to the
database using a named pipe.
Not applicable for TPT API since TPT API transfers the
buffers without staging any data.
Initial maximum rate in a minute at which the TPump
executable sends statements to the Teradata database.
Not applicable for TPT API sessions since TPT API
does not allow the user to control the statement rate.
Session
Determines whether operations on a given key
combination of rows occur serially.
Enable serialize if the job contains multiple changes to
one row. Sessions that contain multiple partitions with
the same key range but different filter conditions may
cause multiple changes to a single row. Enable
Serialize to prevent locking conflicts in the Teradata
database, especially if you set the Pack attribute to a
value greater than 1.
If you enable Serialize, the Integration Service uses the
primary key specified in the target table as the Key
column. If no primary key exists in the target table,
clear this option.
TPump Property
TPT API Property
Session/
Connection
Description
Error Database
Error Database
Session
Error database name. Use this attribute to override the
default error database name. If you do not specify a
database name, the Integration Service uses the target
table database.
Work Table
Database
Work Table Database
Session
Work table database name. Use this attribute to
override the default work table database name. If you
do not specify a database name, the Integration
Service uses the target table database
Log Table Database
Log Database
Session
Log table database name. Use this attribute to override
the default log table database name. If you do not
specify a database name, the Integration Service uses
the target table database.
User Variables
n/a
Error Table
Error Table Name 1
Session
Table name for the first error table overrides the default
error table name. If you do not specify an error table
name, the Integration Service uses
ET_<target_table_name>.
Log Table
Log Table Name 1
Session
Log table name. Use this attribute to override the
default log table name. If you do not specify a log table
name, the Integration Service uses
TL_<target_table_name><partition_number>.
Control File Content
Override
n/a
User-defined variable used in the default control file.
Not applicable for TPT API since TPT API does not use
control file.
Control file text. Use this attribute to override the
control file the Integration Service uses when it loads to
Teradata.
Not applicable for TPT API sessions. Control file
parameters used by TPump are available as session
properties in TPT API.
Mapping Mload to Dual Load
The following table describes the mapping of the Mload properties to the Dual Load session and connection properties:
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Mload Property
TPT API Property
Type
Description
TDPID
TDPID
Connection
Host name of the Teradata database.
Database Name
Database Name
Connection
Name of the database to which you want to load
data.
Date Format
n/a
Date format in the the control file. The date format
in the connection object must match the date
format you define in the target definition.
Not applicable for TPT API. In TPT API you cannot
override the date format supported by the mapping
language.
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Mload Property
TPT API Property
Type
Description
Error Limit
Error Limit
Session
Maximum number of rows that TPT API rejects
before it stops loading data to the database table.
Checkpoint
Commit Interval
Session
Number of rows transmitted to the Teradata
database between checkpoints.
Tenacity
Tenacity
Connection
Number of hours TPT API tries to log in to the
required TPT API sessions when the maximum
number of load jobs are already running on the
Teradata database.
Load Mode
n/a
Drop Error Tables
Drop Error Tables
External Loader
Executable
n/a
Max Sessions
Max Sessions
Connection
Maximum number of TPT API sessions per job.
Max Sessions must be between 1 and the total
number of access module processes (AMPs) on
the system.
Sleep
Sleep
Connection
Number of minutes TPT API pauses before
retrying a login. TPT API tries until the login
succeeds or the number of hours specified in the
Tenacity attribute elapses.
Truncate Target Table
Truncate Table
Session
Truncates the target database table before
beginning the job. TPT API cannot load data to
non-empty tables.
Is Staged
n/a
Error Database
Error Database
Session
Error database name. Use this attribute to override
the default error database name. If you do not
specify a database name, the Integration Service
uses the target table database.
Work Table Database
Work Table Database
Session
Work table database name. Use this attribute to
override the default work table database name. If
you do not specify a database name, the
Integration Service uses the target table database.
Mode to generate SQL commands: Insert, Delete,
Update, Upsert, or Data Driven.
Not applicable for TPT API since TPT API does not
use control file. To flag the rows for upsert, you
can use the session property Update Else Insert.
Session
Drops the error tables before beginning the next
session. The session fails if non-empty error tables
exist from a prior job.
Name and optional file path of the Teradata
external loader executable.
Not applicable for TPT API since TPT API
transfers the buffers without staging any data.
Method of loading data. Select Is Staged to load
data to a flat file staging area before loading to the
database. Otherwise, the data is loaded to the
database using a named pipe.
Not applicable for TPT API since TPT API
transfers the buffers without staging any data.
Mload Property
TPT API Property
Type
Description
In TPT API, the attribute is applicable to the
Update operator.
Log Table Database
Log Database
Session
Log table database name. Use this attribute to
override the default log table database name. If
you do not specify a database name, the
Integration Service uses the target table database.
User Variables
n/a
Error Table 1
Error Table Name 1
Session
Table name for the first error table overrides the
default error table name. If you do not specify an
error table name, the Integration Service uses
ET_<target_table_name>.
Error Table 2
Error Table Name 2
Session
Table name for the second error table overrides
the default error table name. If you do not specify
an error table name, the Integration Service uses
UV_<target_table_name>.
Control File Content
Override
n/a
User-defined variable used in the default control
file.
Not applicable for TPT API since TPT API does not
use control file.
Control file text. Use this attribute to override the
control file the Integration Service uses when it
loads to Teradata.
Not applicable for TPT API.
Mapping FastLoad to Dual Load
The following table describes the mapping of the FastLoad properties to the Dual Load session and connection properties:
9
FastLoad Property
TPT API Property
Type
Description
TDPID
TDPID
Connection
Host name of the Teradata database.
Database Name
Database Name
Connection
Name of the database to which you want to load data.
Error Limit
Error Limit
Session
Maximum number of rows that TPT API rejects before it stops
loading data to the database table.
Checkpoint
Commit Interval
Session
Number of rows transmitted to the Teradata database between
checkpoints.
Tenacity
Tenacity
Connection
Number of hours TPT API tries to log in to the required TPT
API sessions when the maximum number of load jobs are
already running on the Teradata database.
Drop Error Tables
Drop Error Tables
Session
Drops the error tables before beginning the next session. The
session fails if non-empty error tables exist from a prior job.
External Loader
Executable
n/a
Name and optional file path of the Teradata external loader
executable.
Not applicable for TPT API since TPT API transfers the buffers
without staging any data.
FastLoad Property
TPT API Property
Type
Description
Max Sessions
Max Sessions
Connection
Maximum number of FastLoad sessions in a job. Max Sessions
must be between 1 and the total number of access module
processes (AMPs) on the system.
Sleep
Sleep
Connection
Number of minutes TPT API pauses before retrying a login.
TPT API tries until the login succeeds or the number of hours
specified in the Tenacity attribute elapses.
Truncate Target Table
Truncate Table
Session
Truncates the target database table before beginning the job.
TPT API cannot load data to non-empty tables.
Is Staged
n/a
Error Database
Error Database
Session
Error database name. Use this attribute to override the default
error database name. If you do not specify a database name,
the Integration Service uses the target table database.
Error Table 1
Error Table Name 1
Session
Table name for the first error table overrides the default error
table name. If you do not specify an error table name, the
Integration Service uses ET_<target_table_name>.
Error Table 2
Error Table Name 2
Session
Table name for the second error table overrides the default
error table name. If you do not specify an error table name, the
Integration Service uses UV_<target_table_name>.
Control File Content
Override
n/a
Loads data to a flat file staging area before loading to the
database. Otherwise, the data is loaded to the database using
a named pipe.
Not applicable for TPT API since TPT API transfers the buffers
without staging any data.
Control file text. Fastload uses this attribute to override the
control file the Integration Service uses when it loads to
Teradata.
Not applicable for TPT API. Control file parameters used by
Fastload are available as session properties in TPT API.
Mapping FastExport to TPT API
The following table describes the mapping of the FastExport properties to the TPT API session and connection properties:
FastLoad Property
TPT API Property
Type
Description
TDPID
TDPID
Connection
Host name of the Teradata database.
Tenacity
Tenacity
Connection
Number of hours TPT API tries to log in to the required TPT
API sessions when the maximum number of load jobs are
already running on the Teradata database.
Max Sessions
Max Sessions
Connection
Maximum number of TPT API sessions per job. Max Sessions
must be between 1 and the total number of access module
processes (AMPs) on the system.
Sleep
Sleep
Connection
Number of minutes TPT APIpauses before retrying a login.
TPT API tries until the login succeeds or the number of hours
specified in the Tenacity attribute elapses.
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FastLoad Property
TPT API Property
Type
Description
Block Size
Block Size
Connection
Maximum block size to use for the exported data.
Data Encryption
Data Encryption
Connection
Encrypts data that you want to load. You can use data
encryption with the Teradata 8 client.
Log table Name
n/a
Restart log table name. The FastExport utility uses the
information in the restart log table to restart jobs that halt
because of a Teradata database or client system failure.
Not applicable for TPT API. You can configure Error/Log/Work
databases and tables in TPT API through session properties.
Executable Name
n/a
Teradata command used to read the source data. Not
applicable to TPT API ,since TPT API transfers the buffers
directly without landing any data.
Database name
Database name
Control File Content
Override
n/a
Connection
The name of the Teradata database you want to connect. The
Integration Service generates the SQL statement using the
database name as a prefix to the table name.
Control file text. FastExport uses this attribute to override the
control file the Integration Service uses when it loads to
Teradata.
Not applicable for TPT API. Control file parameters used by
FastExport are available as session properties in TPT API.
Limitations of Dual Load over External Loaders
Dual Load sessions have the following limitations which are not applicable to the external loaders:
¨ You can use user defined functions (UDF) in the control file with external loaders. UDFs are not supported by Dual
Load.
¨ External loaders and FastExport supports all the codepages supported by PowerCenter.Teradata PT API supports
only the following codepages:
- UTF-8 encoding of Unicode
- MS Windows Latin 1 (ANSI) superset of Latin1
- MS Windows Japanese, superset of Shift-JIS
Converting an External Loader Session to a Dual Load Session
1.
11
In the Workflow Manager, open the external loader session that you want to convert.
2.
Change the writer type from File Writer to Teradata Parallel Transporter Writer in the Writers settings on the
Mapping tab.
3.
From the Connections settings on the Targets node, select a Teradata Dual Load Connection.
4.
From the Connections settings on the Targets node of the Mapping tab, configure the Teradata PT API target
properties.
When you configure the target properties, provide the same values as in the loader connection.
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Teradata PT API Target Properties
Configure the Teradata PT API target properties in a dual load session. The following table describes the Teradata PT API
target properties:
Property
Description
Work Table Database
Name of the database that stores the work tables.
Work Table Name
Name of the work table.
Macro Database
Name of the database that stores the macros that Teradata PT API creates when you select the Stream
system operator in the connection object.
The Stream system operator uses macros to modify tables. It creates macros before Teradata PT API
begins loading data and removes them from the database after Teradata PT API loads all rows to the target.
If you do not specify a macro database, Teradata PT API stores the macros in the log database.
Pause Acquisition
Pauses the load operation before the session loads data to the Teradata PT API target. Disable when you
want to load the data to the target.
Default is disabled.
Instances
The number of parallel instances to load data into the Teradata PT API target.
Default is 1. PowerCenter Dual Load Option for Teradata does not support multiple instances.
Query Band
Expression
The query band expression that the PowerCenter Integration Service passes to the Teradata PT API.
A query band expression is a set of name-value pairs that identify the originating source of a query. In the
expression, each name-value pair is separated by a semicolon, and the expression ends with a semicolon.
For example, ApplicationName=Informatica;Version=9.0.1;ClientUser=A;
Update Else Insert
Teradata PT API updates existing rows and inserts other rows as if marked for update. If disabled,
Teradata PT API updates existing rows only.
The PowerCenter Integration Service ignores this attribute when you treat source rows as inserts or deletes.
Default is disabled.
Truncate Table
Teradata PT API deletes all rows in the Teradata target before it loads data.
This attribute is available for the Update and Stream system operators. It is available for the Load system
operator if you select a Teradata target ODBC connection.
Default is disabled.
Mark Missing Rows
Specifies how Teradata PT API handles rows that do not exist in the target table:
- None. If Teradata PT API receives a row marked for update or delete that is missing in the target table,
Teradata PT API does not mark the row in the error table.
- For Update. If Teradata PT API receives a row marked for update that is missing in the target table,
Teradata PT API marks the row as an error row.
- For Delete. If Teradata PT API receives a row marked for delete that is missing in the target table,
Teradata PT API marks the row as an error row.
- Both. If Teradata PT API receives a row marked for update or delete that is missing in the target table,
Teradata PT API marks the row as an error row.
Default is None.
Mark Duplicate Rows
Specifies how Teradata PT API handles duplicate rows when it attempts to insert or update rows in the
target table:
- None. If Teradata PT API receives a row marked for insert or update that causes a duplicate row in the
target table, Teradata PT API does not mark the row in the error table.
- For Insert. If Teradata PT API receives a row marked for insert but it exists in the target table,
Teradata PT API marks the row as an error row.
- For Update. If Teradata PT API receives a row marked for update that causes a duplicate row in the
target table, Teradata PT API marks the row as an error row.
- Both. If Teradata PT API receives a row marked for insert or update that causes a duplicate row in the
target table, Teradata PT API marks the row as an error row.
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Property
Description
Default is For Insert.
Log Database
Name of the database that stores the log tables.
Log Table Name
Name of the restart log table.
Error Database
Name of the database that stores the error tables.
Error Table Name1
Name of the first error table.
Error TableName2
Name of the second error table.
Drop Log/Error/Work
Tables
Drops existing log, error, and work tables for a session when the session starts.
This attribute is available if you select a Teradata target ODBC connection.
Default is disabled.
Serialize
Uses the Teradata PT API serialize mechanism to reduce locking overhead when you select the Stream
system operator.
Default is enabled.
Pack
Number of statements to pack into a request when you select the Stream system operator.
Must be a positive integer.
Default is 20. Minimum is 1. Maximum is 600.
Pack Maximum
Causes the Teradata PT API to determine the maximum number of statements to pack into a request when
you select the Stream system operator.
Default is disabled.
Buffers
Determines the maximum number of request buffers that may be allocated for the Teradata PT API job
when you select the Stream system operator. Teradata PT API determines the maximum number of request
buffers according to the following formula:
Max_Request_Buffers = Buffers * Number_Connected_Sessions
Must be a positive integer.
Default is 3. Minimum is 2.
Error Limit
Maximum number of records that can be stored in the error table before the Teradata PT API terminates the
Stream system operator job.
Must be -1 or a positive integer.
Default is -1, which specifies an unlimited number of records.
Replication Override
Specifies how Teradata PT API overrides the normal replication services controls for an active Teradata PT
API session:
- On. Teradata PT API overrides normal replication services controls for the active session.
- Off. Teradata PT API disables override of normal replication services for the active session when
change data capture is active.
- None. Teradata PT API does not send an override request to the Teradata database.
Default is None.
Driver Tracing Level
Determines Teradata PT API tracing at the driver level:
- TD_OFF. Teradata PT API disables tracing.
- TD_OPER. Teradata PT API enables tracing for driver-specific activities for Teradata.
- TD_OPER_ALL. Teradata PT API enables all driver-level tracing.
- TD_OPER_CLI. Teradata PT API enables tracing for activities involving CLIv2.
- TD_OPER_NOTIFY. Teradata PT API enables tracing for activities involving the Notify feature.
- TD_OPER_OPCOMMON. Teradata PT API enables tracing for activities involving the operator common
library.
Default is TD_OFF.
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Property
Description
Infrastructure Tracing
Level
Determines Teradata PT API tracing at the infrastructure level:
- TD_OFF. Teradata PT API disables tracing.
- TD_OPER. Teradata PT API enables tracing for driver-specific activities for Teradata.
- TD_OPER_ALL. Teradata PT API enables all driver-level tracing.
- TD_OPER_CLI. Teradata PT API enables tracing for activities involving CLIv2.
- TD_OPER_NOTIFY. Teradata PT API enables tracing for activities involving the Notify feature.
- TD_OPER_OPCOMMON. Teradata PT API enables tracing for activities involving the operator common
library.
Default is TD_OFF.
You must enable the driver tracing level before you can enable the infrastructure tracing level.
Trace File Name
File name and path of the Teradata PT API trace file. Default path is $PM_HOME. Default file name is
<Name of the TPT Operator>_timestamp. For example, LOAD_20091221.
Scenario: Migration from Single Loader Session to Dual Load
Session
The following scenario describes how to migrate a single loader session with FastLoad external loader to a dual load session.
The hourly call data received by the technical support team is aggregated in a Teradata database for further analysis. The
existing system uses FastLoad to load data in to the Teradata database. The mapping, m_cust_agg maps the source
cust_acct_hrly_agg to the target cust_acct_agg.
The workflow wf_hrly_fastload_workflow loads data to the Teradata system with the session s_hrly_fastload. The session
uses FastLoad to load data to the Teradata target.
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Perform the following steps to migrate the FastLoad session to a dual load session.
1.
Right-click on s_hrly_fastload and click Duplicate to create a copy of s_hrly_fastload.
2.
Rename the object if required.
3.
Configure the dual load connection properties with the properties used in the FastLoad configuration.
4.
In the Target section of the Mapping properties of the session, change the Writer to Teradata Parallel Transporter
Writer from File Writer.
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5.
Select Teradata_Dual_Load_Connection as the relational connection.
6.
Configure the dual load session properties with the properties used in the FastLoad configuration.
7.
In the dual load workflow, replace UserSession with s_hrly_dualload.
8.
Click Workflow Workflow > Edit.
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.
9.
On the Variables tab, enter the details of the dual load environment.
Author
Narayan Sivaramakrishnan
Technical Writer
Acknowledgements
The author would like to acknowledge Rajeeva Lochan Yellanki, Anudeep Sharma, and Diby Malakar.
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