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 fields that follow are
completed automatically using the data retrieved.

Click this icon to open a database connection wizard and store the
database connection parameters you set in the component Basic settings view.

For more information about setting up and storing database
connection parameters, see
Talend Studio User Guide.

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.

DB Version

List of database versions.

Host

Database server IP address.

Port

Listening port number of DB server.

Database

Name of the database.

Schema

Exact name of the schema.

Username and
Password

DB user authentication data.

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.

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.

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.

This
component offers the advantage of the dynamic schema feature. This allows you to
retrieve unknown columns from source files or to copy batches of columns from a source
without mapping each column individually. For further information about dynamic schemas,
see
Talend Studio

User Guide.

This
dynamic schema feature is designed for the purpose of retrieving unknown columns of a
table and is recommended to be used for this purpose only; it is not recommended for the
use of creating tables.

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.

Table name

Name of the table to be read.

Query type and
Query

Enter your DB query paying particularly attention to properly
sequence the fields in order to match the schema definition.

If using the dynamic schema feature, the SELECT query
must include the * wildcard,
to retrieve all of the columns from the table selected.

Additional JDBC Parameters

Specify additional JDBC parameters for the
database connection created.

This property is not available when the Use an existing connection
check box in the Basic settings view is selected.

Use cursor

When selected, helps to decide the row set to work with at a time
and thus optimize performance.

Trim all the String/Char columns

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

Trim column

Remove leading and trailing whitespace from defined
columns.

tStat
Catcher Statistics

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

Global Variables

NB_LINE: the number of rows read by an input component or
transferred to an output component. 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.

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.

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

Usage rule

This component covers all possible SQL queries for Postgresql
databases.

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.