tPostgresPlusSCDELT - 6.3

Talend Open Studio for Big Data Components Reference Guide

EnrichVersion
6.3
EnrichProdName
Talend Open Studio for Big Data
task
Data Governance
Data Quality and Preparation
Design and Development
EnrichPlatform
Talend Studio

Function

tPostgresPlusSCDELT reflects and tracks changes in a dedicated Oracle SCD table.

Purpose

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

tPostgresPlusSCDELT Properties

Component family

Databases/PostgresPlus

 

Basic settings

Property type

Either Built-in or Repository.

Since version 5.6, both the Built-In mode and the Repository mode are available in any of the Talend solutions.

 

 

Built-in: No property data stored centrally. Enter properties manually.

 

 

Repository: Select the repository file where Properties are stored. The fields that come after are pre-filled in using the fetched data.

 

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.

 

DB Version

List of database versions.

 

Host

The IP address of the database server.

 

Port

Listening port number of database server.

 

Database

Name of the database.

 

Schema

Exact name of the schema

 

Username and Password

User authentication data for a dedicated 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

Name of the input DB2 SCD table.

 

Table

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

 

Action on table

Select to perform one of the following operations on the table defined:

None: No action carried out on the table.

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

Create table: A new table gets created.

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

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.

 

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. The schema is either Built-In or stored remotely in the Repository.

Since version 5.6, both the Built-In mode and the Repository mode are available in any of the Talend solutions.

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.

 

 

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.

 

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 regarding the creation methods, see SCD keys.

 

Source Keys

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

 

Use SCD Type 1 fields

Use type 1 if tracking changes is not necessary. SCD Type 1 should be used for typos corrections for example. Select the columns of the schema that will be checked for changes.

 

Use SCD Type 2 fields

Use type 2 if changes need to be tracked down. SCD Type 2 should be used to trace updates for example. Select the columns of the schema that will be checked for changes.

Start date: Adds a column to your SCD schema to hold the start date value. You can select one of the input schema columns as Start Date in the SCD table.

End Date: Adds a column to your SCD schema to hold the end date value for the record. When the record is currently active, the End Date column shows a null value, or you can select Fixed Year value and fill it in with a fictive year to avoid having a null value in the End Date field.

Log Active Status: Adds a column to your SCD schema to hold the true or false status value. This column helps to easily spot the active record.

Log versions: Adds a column to your SCD schema to hold the version number of the record.

Advanced settings

Debug mode

Select this check box to display each step during processing entries in a database.

 

tStatCatcher Statistics

Select this check box to collect log data at the component level.

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 Scenario 3: Reading data from MySQL databases through context-based dynamic connections and Scenario: 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.

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

This component is used as an output component. It requires an input component and Row main link as input.

Related Scenario

For related topics, see tMysqlSCD.