July 30, 2023

tTeradataSCDELT – Docs for ESB 7.x

tTeradataSCDELT

Addresses Slowly Changing Dimension needs through SQL queries (server-side
processing mode), and logs the changes into a dedicated Teradata SCD table.

tTeradataSCDELT
reflects and tracks changes in a dedicated Teradata SCD table.

tTeradataSCDELT Standard properties

These properties are used to configure tTeradataSCDELT running in the Standard Job
framework.

The Standard
tTeradataSCDELT component belongs to the Business Intelligence and the Databases families.

The component in this framework is available in all Talend
products
.

Note: This component is a specific version of a dynamic database
connector. The properties related to database settings vary depending on your database
type selection. For more information about dynamic database connectors, see Dynamic database components.

Basic settings

Database

Select a type of database from the list and click
Apply.

Property Type

Either Built-In or Repository.

  • Built-In: No
    property data stored centrally.

  • Repository: Select
    the repository file in which the properties are stored. The database
    connection fields that follow are completed automatically using the data
    retrieved.

Use an existing
connection

Select this check box and in the Component List click the relevant connection component to
reuse the connection details you already defined.

Note: When a Job contains the parent Job and the child Job, if you
need to share an existing connection between the two levels, for example, to share the
connection created by the parent Job with the child Job, you have to:

  1. In the parent level, register the database connection
    to be shared in the Basic
    settings
    view of the connection component which creates that very database
    connection.

  2. In the child level, use a dedicated connection
    component to read that registered database connection.

For an example about how to share a database connection
across Job levels, see

Talend Studio
User Guide
.

Host

Enter the IP address or hostname of the
database server.

Database

Enter the name of the database you want to
use.

Username and Password

Enter the user authentication data to access
the database.

To enter the password, click the […] button next to the
password field, and then in the pop-up dialog box enter the password between double quotes
and click OK to save the settings.

Source table

Enter the name of the input Teradata SCD
table.

Table

Enter the name of the table to be written. Note
that only one table can be written at a time.

Action on table

Select one of the following operations to be
performed on the table defined:

  • None: No action
    carried out on the table.

  • Create table: A
    new table gets created.

  • Drop and create
    table
    : The table is removed and created again.

  • Create table if not
    exists
    : A table gets created if it does not exist.

  • Drop table if exists and
    create
    : The table is removed if it already exists and
    created again.

  • Clear table: The
    table content is deleted. You have the possibility to rollback the
    operation.

  • Truncate table:
    The table content is deleted. You don not have the possibility to
    rollback the operation.

Create

Select the type of the table to be created:

  • SET TABLE: creates
    a SET table that does not allow duplicate rows to be inserted.

  • MULTISET TABLE:
    creates a MULTISET table that allows duplicate rows to be inserted.

This list is available only when Create table, Drop and create table,
Create table if not
exists
, or Drop
table if exists and create
is selected from the Action on table drop-down
list.

Schema and Edit schema

A schema is a row description. It defines the number of fields
(columns) to be processed and passed on to the next component. When you create a Spark
Job, avoid the reserved word line when naming the
fields.

  • Built-In: The
    schema is created and stored locally for this component only. Related
    topic: see
    Talend Studio User Guide
    .

  • Repository: The
    schema already exists and is stored in the Repository, hence can be
    reused. Related topic: see
    Talend Studio User Guide
    .

 

Click Edit
schema
to make changes to the schema. If the current schema is of the Repository type, three options are available:

  • View schema: choose this
    option to view the schema only.

  • Change to built-in property:
    choose this option to change the schema to Built-in for local changes.

  • Update repository connection:
    choose this option to change the schema stored in the repository and decide whether
    to propagate the changes to all the Jobs upon completion. If you just want to
    propagate the changes to the current Job, you can select No upon completion and choose this schema metadata
    again in the Repository Content
    window.

Surrogate key

Select the surrogate key column from the
list.

Creation

Select the method to be used for the surrogate
key generation.

For more information about the creation
methods, see SCD management methodology.

Source Keys

Select one or more columns to be used as keys,
to ensure the unicity of the incoming data.

Use SCD type 1 fields

Select this check box to use SCD Type 1 if
tracking changes is not necessary. SCD Type 1 should be used for typos
corrections for example.

SCD type 1 fields

Click the [+] button to add as many rows as needed, and
in each row select an input schema column that will be checked for Type 1
changes.

This table is available only when the
Use SCD type 1
fields
check box is selected.

Use SCD type 2 fields

Select this check box to use SCD Type 2 if
changes need to be tracked down. SCD Type 2 should be used to trace updates for
example.

SCD type 2 fields

Click the [+] button to add as many rows as needed, each row for a column. Click
the arrow on the right side of the cell and select the column whose value changes will
be tracked using Type 2 SCD from the drop-down list displayed .

This table is available only when the Use SCD type 2 fields
option is selected.

Start date

Specify the column that holds the start date for
type 2 SCD.

This list is available only when the Use SCD type 2 fields
option is selected.

End date

Specify the column that holds the end date for type
2 SCD.

This list is available only when the Use SCD type 2 fields
option is selected.

Note: To avoid duplicated change records, it is recommended to
select a column that can identify each change for this field.

Log active status

Select this check box and from the
Active field drop-down list displayed, select
the column that holds the true or false status value, which helps to spot the active
record for type 2 SCD.

This option is available only when the Use SCD type 2 fields
option is selected.

Log versions

Select this check box and from the Version field drop-down list displayed, select the column
that holds the version number of the record for type 2 SCD.

This option is available only when the Use SCD type 2 fields
option is selected.

Advanced settings

Additional JDBC
Parameters

Specify additional connection properties for
the database connection you are creating.

This field is not available if the Use an existing connection
check box is selected.

Source fields value include
Null

Select this check box to allow the source
columns to have Null values. The source columns here refer to the fields
defined in the SCD type 1
fields
and SCD type
2 fields
tables.

tStatCatcher Statistics

Select this check box to gather the Job
processing metadata at the Job level as well as at each component level.

Global Variables

Global Variables

ERROR_MESSAGE: the error message generated by the
component when an error occurs. This is an After variable and it returns a string. This
variable functions only if the Die on error check box is
cleared, if the component has this check box.

A Flow variable functions during the execution of a component while an After variable
functions after the execution of the component.

To fill up a field or expression with a variable, press Ctrl +
Space
to access the variable list and choose the variable to use from it.

For further information about variables, see
Talend Studio

User Guide.

Usage

Usage rule

This component is used as an output component
and it always needs an incoming link.

Dynamic settings

Click the [+] button to add a row in the table
and fill the Code field with a context
variable to choose your database connection dynamically from multiple
connections planned in your Job. This feature is useful when you need to
access database tables having the same data structure but in different
databases, especially when you are working in an environment where you
cannot change your Job settings, for example, when your Job has to be
deployed and executed independent of Talend Studio.

The Dynamic settings table is
available only when the Use an existing
connection
check box is selected in the Basic settings view. Once a dynamic parameter is
defined, the Component List box in the
Basic settings view becomes unusable.

For examples on using dynamic parameters, see Reading data from databases through context-based dynamic connections and Reading data from different MySQL databases using dynamically loaded connection parameters. For more information on Dynamic
settings
and context variables, see Talend Studio
User Guide.

Limitation

This component requires installation of its related jar files.


Document get from Talend https://help.talend.com
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