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

Common Database Syntax Restrictions

Common Database Syntax Restrictions

Different databases have different restrictions on outer join syntax. Consider the following restrictions when you create outer joins:
  • Do not combine join conditions with the OR operator in the ON clause of outer join syntax.
  • Do not use the IN operator to compare columns in the ON clause of outer join syntax.
  • Do not compare a column to a subquery in the ON clause of outer join syntax.
  • When combining two or more outer joins, do not use the same table as the inner table of more than one outer join. For example, do not use either of the following outer joins:
    { TABLE1 LEFT OUTER JOIN TABLE2 ON TABLE1.COLUMNA = TABLE2.COLUMNA TABLE3 LEFT OUTER JOIN TABLE2 ON TABLE3.COLUMNB = TABLE2.COLUMNB } { TABLE1 LEFT OUTER JOIN TABLE2 ON TABLE1.COLUMNA = TABLE2.COLUMNA TABLE2 RIGHT OUTER JOIN TABLE3 ON TABLE2.COLUMNB = TABLE3.COLUMNB}
  • Do not use both tables of an outer join in a regular join condition. For example, do not use the following join condition:
    { TABLE1 LEFT OUTER JOIN TABLE2 ON TABLE1.COLUMNA = TABLE2.COLUMNA WHERE TABLE1.COLUMNB = TABLE2.COLUMNC}
    However, use both tables in a filter condition, like the following:
    { TABLE1 LEFT OUTER JOIN TABLE2 ON TABLE1.COLUMNA = TABLE2.COLUMNA WHERE TABLE1.COLUMNB = 32 AND TABLE2.COLUMNC > 0}
    Entering a condition in the ON clause might return different results from entering the same condition in the WHERE clause.
  • When using an alias for a table, use the alias to prefix columns in the table. For example, if you call the REG_CUSTOMER table C, when referencing the column FIRST_NAME, use “C.FIRST_NAME.”

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