Database

Enter the connection string that contains the database. For
details, 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.

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

Name of the table to be processed.

Query type

Either Built-in or Repository.

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 Guess Query button to
generate the query which corresponds to your table schema in the
Query field.

Query

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

Die on error

This check box is selected by default. Clear the check box to skip
the row on error and complete the process for error-free rows. If
needed, you can retrieve the rows on error via a Row > Rejects link.

Propagate QUERY’s recordset

Select this check box to insert the result of the query in a
COLUMN of the current flow. Select this column from the use column list.

Use PreparedStatement

Select this check box if you want to query the database using a
PreparedStatement. In the Set
PreparedStatement Parameter table, define the
parameters.

Parameter Index: Enter the
parameter position in the SQL instruction.

Parameter Type: Enter the parameter
type.

Parameter Value: Enter the
parameter value.

tStatCatcher Statistics

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

Global Variables

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 rule

This component offers the flexibility of the database query and
covers all possible SQL queries.

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: Reading data from 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.