Output page for classicfedread operations

On this page, use the tabs to specify the properties to perform a classicfedread operation.

General tab

On the General tab, enter an optional description for the classicfedread operation.

Properties tab

On the Properties tab, specify properties for the output link. The properties determine the data source, the operation to be performed on the data, the input resource, and so on. The following table lists the properties and their attributes. A more detailed description of each property follows.

Table 1. Source category properties of the Output page for ClassicFedRead operations
Property Values Default value Required? Property dependent on
Table Table name N/A Yes N/A
Read method
  • Auto-generated SQL
  • Table
  • User-defined SQL
Table Yes N/A
Query Select Statement N/A Yes Read method
Table
  • Select List
  • Where Clause
N/A Yes Read method
Select list List of columns N/A Yes Table
Where clause Rows of a table N/A Yes Table
Table 2. Connection category properties of the Output page for ClassicFedRead operations
Property Value Default value Required? Property dependent on
Data source Data source name N/A Yes N/A
User User name N/A Yes Data source
Password Password N/A Yes Data source
Table 3. Options category properties of the Output page for ClassicFedRead operations
Property Value Default value Required? Property dependent on
Fetch array size Integer 1 Yes N/A
Open command SQL statement No Yes N/A
Close command SQL statement No Yes N/A
Isolation level
  • Read Uncommitted
  • Read Committed
  • Repeatable Read
  • Serializable
Read Uncommitted Yes N/A

Source category

Specify the values for Read Method, Query, and Table:

Read Method
Specify a table or a query for reading the database. The default value is Table. If you select Table, you must specify the data source table for the Table option. Alternatively, you can set up Read Method as an SQL query. In that case, you must specify whether you want the query to be generated automatically or you want to define the query yourself.
Note: The Query property is displayed on the list of properties only when you select Auto-generated SQL or User-defined SQL as the Read method. To select one of these types of query, click Read Method, and then select the appropriate option from the Read Method list on the right side of the properties list.
Query
Specify an SQL statement for reading a table. The statement specifies the table to read and the processes to perform on the table during the ClassicFedRead operation. This statement can contain join and view operations, database links, synonyms, and so on. Choose from the following values:
  • Auto-generated SQL: Specify that an SQL query is generated automatically that is based on the table that you specify in the Table field and the columns that you define.
  • User-defined SQL: Define a custom SQL query.
    Note: An SQL query is read sequentially on one node.
Table
When you select Table as the read method, specify the name of the source table on the federated system. The specified table must exist, and you must have SELECT privileges for this table. If your federated user name does not correspond to the owner of the specified table, you can prefix it with a table owner. You must add a new job parameter to fix the table owner name.

To fix the table owner name:

  1. Click Table and then the arrow on the right side of the dialog.
  2. Use the WHERE clause in your SELECT statement to specify the rows of the table to be included or excluded from the read operation. If you do not supply a WHERE clause, all rows are read.
  3. Click Insert job parameter and then [New...] from the list.
  4. You can specify in your SELECT statement the columns that you want to read. You must specify the columns in this list in the same order as they are defined in the record schema of the input table.
  5. In the Job Properties dialog enter the required table details in Default Value column for the user parameter in this format:
    table_owner.table_name

Connection category

Specify the Data source, Password, and User values:

Data source
This is a required field. Specify the database connection in this field by using any one of the following methods:
  • Enter the data source name in the Data source field on the right side of the Properties page.
  • Insert the required value as a job parameter. Click the pointer button on the extreme right side of the Properties page, and then click Insert Job Parameters.

    A list of available job parameters is displayed. To create a new parameter for the job, click [New...] from the list and create an appropriate environment variable in the Job Properties dialog.

User
This is an optional field. Specify the user name for connecting to the data source by using any one of the following methods:
  • Enter the user name in the User field on the right side of the Properties page.
  • Insert the desired value as a job parameter. Click the pointer button on the extreme right side of the Properties page, and then click Insert Job Parameters.

    A dialog appears with a list of available job parameters. To create a new parameter for the job, click [New...] from the list and create an appropriate environment variable in the Job Properties dialog.

    Note: If you insert all or some of the Connection category values from the job parameter list, then the job takes the environment variables from the operating system. At run time, you are prompted to modify the values for those environment variables.
Password
This is an optional field. Specify the password for connections to the data source with one of these methods:
  • Enter the password in the Password field on the right side of the Properties page.
  • Insert the required value as a job parameter. Click the pointer button on the extreme right side of the Properties page, and then click Insert Job Parameters.

    A dialog appears with a list of available job parameters. To create a new parameter for the job, click [New...] from the list and create an appropriate environment variable with the Job Properties dialog.

Options category

Specify values for the FetchArraySize, Isolation Level, Close Command, and Open Command properties. All of these properties are optional. You see these properties in the Available properties to add list that appears in the lower right corner of the Output page. To add these subproperties, click Options, and then click the property that you want to add from the Available properties to add list.

Fetch Array Size
Specify the number of rows to retrieve during each fetch operation. The default value is 1.
Isolation Level
Enter the isolation level for accessing data.

The database for the Data source property determines the default isolation level.

Close Command
Enter an SQL statement to be run after the insert array is processed. You cannot commit work with this property. The statements are run only once on the conductor node.
Open Command
Enter an SQL statement to be run before the insert array is processed. The statements are run only once on the conductor node.
Note: With IBM® InfoSphere® DataStage® and QualityStage® Administrator, you can create parameters at the project level for all jobs within the project.

Advanced tab

Use the Advanced tab to specify how input and output data for the stage is buffered. By default, data is buffered so that no deadlocks can arise.

Columns button

Use the Columns button to define a list of column names for the output table.

View Data button

To view the number of rows in the table that you specified for the Table property under Source, click the View Data button. You can specify the number of rows that you want to view at a time.