tOleDbInput - 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

This component reads a database and extracts fields based on a query. It offers the flexibility benefit of the DB query and covers all possible SQL queries.

Purpose

This component executes a DB query with a strictly defined order which must correspond to the schema definition. Then it passes on the field list to the next component via a Main row link.

tOleDbInput properties

Component family

Databases/OleDb

 

Basic settings

Connection URL

Enter the connection string used to open the database. For details, please see http://msdn.microsoft.com/en-us/library/system.data.oledb.oledbconnection.connectionstring.aspx.

 

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.

 

 

Built-In: You create and store the schema locally for this component only. Related topic: see Talend Studio User Guide.

 

 

Repository: You have already created the schema and stored it in the Repository. You can reuse it in various projects and Job designs. 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.

 

Table Name

Enter the name of the table to be processed.

 

Query Type

Select either Built-in or Repository query type from the drop-down list.

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

 

 

Built-in: Fill in manually the query statement or build it graphically using SQLBuilder.

 

 

Repository: Select the relevant query stored in the Repository. The Query field gets accordingly filled in.

 

Guess Query

Click the button to generate the query which corresponds to the defined table schema in the Query field.

 

Guess schema

Click the button to retrieve the schema from the table.

 

Query

Specify the database query paying particularly attention to properly sequence the fields in order to match the schema definition.

Advanced settings

Trim all the String/Char columns

Select this check box to remove leading and trailing whitespace from all the String/Char columns.

 

Trim column

Select the check box in Trim column to remove leading and trailing whitespace from the corresponding column.

This field appears only when the Trim all the String/Char columns check box is cleared.

 

tStatCatcher Statistics

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

Global Variables

NB_LINE: the number of rows processed. This is an After variable and it returns an integer.

QUERY: the query statement being processed. This is a Flow variable and it returns a string.

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 a start component in a Job and it always needs an output link.

Log4j

If you are using a subscription-based version of the Studio, the activity of this component can be logged using the log4j feature. For more information on this feature, see Talend Studio User Guide.

For more information on the log4j logging levels, see the Apache documentation at http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/Level.html.

Related scenario

For similar scenarios, see tMysqlInput.