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 Query

Default Query

For relational sources, the Integration Service generates a query for each Source Qualifier transformation when it runs a session. The default query is a SELECT statement for each source column used in the mapping. In other words, the Integration Service reads only the columns that are connected to another transformation.
The following figure shows a single source definition connected to a Source Qualifier transformation, with many source definition columns but only three connected to the final transformation:
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Although there are many columns in the source definition, only three columns are connected to another transformation. In this case, the Integration Service generates a default query that selects only those three columns:
SELECT CUSTOMERS.CUSTOMER_ID, CUSTOMERS.COMPANY, CUSTOMERS.FIRST_NAME FROM CUSTOMERS
If any table name or column name contains a database reserved word, you can create and maintain a file, reswords.txt, containing reserved words. When the Integration Service initializes a session, it searches for reswords.txt in the Integration Service installation directory. If the file exists, the Integration Service places quotes around matching reserved words when it executes SQL against the database. If you override the SQL, you must enclose any reserved word in quotes.
When generating the default query, the Designer delimits table and field names containing the following characters with double quotes:
/ + - = ~ ` ! % ^ & * ( ) [ ] { } ' ; ? , < > \ | <space>

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