16.20 - Simple Data Conditioning in the SELECT Statement - Parallel Transporter

Teradata® Parallel Transporter User Guide

Product
Parallel Transporter
Release Number
16.20
Published
August 2020
Language
English (United States)
Last Update
2020-08-27
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Teradata PT scripts can accomplish a variety of simple data conditioning tasks. Conditioning tasks that do not require a filter operator are specified in the executable section of the job script.

The following table contains some examples of data conditioning using SELECT and the syntax for each.

Data Conditioning Syntax Using SELECT 
Filtering Task Code Example
Rename a column from “price” to “original price”
SELECT price AS original_price
Assign new values to a column based on the value of other columns, literals, and arbitrary expressions, such as calculating a discounted price of 20% off the base price.
SELECT price*0.8 AS discounted_price
Assign NULL values to a column.
SELECT NULL(VARCHAR(n)) AS product_name

where n is the size of the VARCHAR column as defined in the DEFINE SCHEMA statement.

Concatenate columns using the concatenation operator (||), such as loading both an area code and the telephone number into the same column to create a customer number
SELECT AREA_CODE||PHONE_NUMBER AS CUSTOMER_NUMBER
Load a value into a column that does not exist in the source, such as putting the value “123” in a column called “JOB_ID”
SELECT '123' as JOB_ID
Assign different values to a column in an output row based on conditions on columns in the corresponding input row, using a CASE value expression.
APPLY 'INSERT INTO SALES_TABLE (original_price, discounted_price, product_name)' TO OPERATOR (UPDATE_OPERATOR [4])
SELECT price AS original_price, price*0.8 AS discounted_price,
CASE WHEN product_name = ' ' THEN NULL(VARCHAR) ELSE product_name
END AS product_name
FROM OPERATOR (DATA_CONNECTOR [2])

For command syntax details, see “APPLY Statement” in Teradata Parallel Transporter Reference (B035-2436).