Table of Contents

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  1. Preface
  2. Working with Transformations
  3. Aggregator Transformation
  4. Custom Transformation
  5. Custom Transformation Functions
  6. Data Masking Transformation
  7. Data Masking Examples
  8. Expression Transformation
  9. External Procedure Transformation
  10. Filter Transformation
  11. HTTP Transformation
  12. Identity Resolution Transformation
  13. Java Transformation
  14. Java Transformation API Reference
  15. Java Expressions
  16. Java Transformation Example
  17. Joiner Transformation
  18. Lookup Transformation
  19. Lookup Caches
  20. Dynamic Lookup Cache
  21. Normalizer Transformation
  22. Rank Transformation
  23. Router Transformation
  24. Sequence Generator Transformation
  25. Sorter Transformation
  26. Source Qualifier Transformation
  27. SQL Transformation
  28. Using the SQL Transformation in a Mapping
  29. Stored Procedure Transformation
  30. Transaction Control Transformation
  31. Union Transformation
  32. Unstructured Data Transformation
  33. Update Strategy Transformation
  34. XML Transformations

Transformation Guide

Transformation Guide

Default Join

Default Join

When you join related tables in one Source Qualifier transformation, the Integration Service joins the tables based on the related keys in each table.
This default join is an inner equijoin, using the following syntax in the WHERE clause:
Source1.column_name = Source2.column_name
The columns in the default join must have:
  • A primary key-foreign key relationship
  • Matching datatypes
For example, you might see all the orders for the month, including order number, order amount, and customer name. The ORDERS table includes the order number and amount of each order, but not the customer name. To include the customer name, you need to join the ORDERS and CUSTOMERS tables. Both tables include a customer ID, so you can join the tables in one Source Qualifier transformation.
The following figure shows joining two tables with one Source Qualifier transformation:
The mapping shows two sources, a Source Qualifier transformation, and an Expression transformation. The sources and the Source Qualifier transformation are open to display port names and datatypes. The Expression transformation is open to display port names and expressions.
When you include multiple tables, the Integration Service generates a SELECT statement for all columns used in the mapping. In this case, the SELECT statement looks similar to the following statement:
SELECT CUSTOMERS.CUSTOMER_ID, CUSTOMERS.COMPANY, CUSTOMERS.FIRST_NAME, CUSTOMERS.LAST_NAME, CUSTOMERS.ADDRESS1, CUSTOMERS.ADDRESS2, CUSTOMERS.CITY, CUSTOMERS.STATE, CUSTOMERS.POSTAL_CODE, CUSTOMERS.PHONE, CUSTOMERS.EMAIL, ORDERS.ORDER_ID, ORDERS.DATE_ENTERED, ORDERS.DATE_PROMISED, ORDERS.DATE_SHIPPED, ORDERS.EMPLOYEE_ID, ORDERS.CUSTOMER_ID, ORDERS.SALES_TAX_RATE, ORDERS.STORE_ID FROM CUSTOMERS, ORDERS WHERE CUSTOMERS.CUSTOMER_ID=ORDERS.CUSTOMER_ID
The WHERE clause is an equijoin that includes the CUSTOMER_ID from the ORDERS and CUSTOMER tables.

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