Table of Contents

Search

  1. Preface
  2. Using the Designer
  3. Working with Sources
  4. Working with Flat Files
  5. Working with Targets
  6. Mappings
  7. Mapplets
  8. Mapping Parameters and Variables
  9. Working with User-Defined Functions
  10. Using the Debugger
  11. Viewing Data Lineage
  12. Comparing Objects
  13. Managing Business Components
  14. Creating Cubes and Dimensions
  15. Using the Mapping Wizards
  16. POWERCENTERHELP
  17. Datatype Reference
  18. Configure the Web Browser

Null Character Handling

Null Character Handling

You can specify single-byte or multibyte null characters for fixed-width file sources. When reading a fixed-width source file, the Integration Service uses these characters to determine if a column is null. When writing to a fixed-width target file, the Integration Service uses these characters to represent null values.
The following table describes how the Integration Service uses the Null Character and Repeat Null Character properties to determine if a column is null:
Null Character
Repeat Null Character
Integration Service Behavior When Reading From Sources and Lookups
Integration Service Behavior When Writing To Targets
Binary
Disabled
A column is null if the first byte in the column is the binary null character. The Integration Service reads the rest of the column as text data to determine the column alignment and track the shift state for shift-sensitive code pages. If data in the column is misaligned, the Integration Service skips the row and writes the skipped row and a corresponding error message to the session log.
Integration Service enters a single binary null character at the beginning of the field to represent a null value.
If there are extra bytes left after writing the null character, the Integration Service pads the column with single-byte spaces.
Non-binary
Disabled
A column is null if the first character in the column is the null character. The Integration Service reads the rest of the column to determine the column alignment and track the shift state for shift sensitive code pages. If data in the column is misaligned, the Integration Service skips the row and writes the skipped row and a corresponding error message to the session log.
Integration Service enters a single null character at the beginning of the field to represent a null value.
If you specify a multibyte null character and there are extra bytes left after writing the null character, the Integration Service pads the column with single-byte spaces. If a column is not big enough to take a null character because it is smaller than the multibyte character specified as the null character, the session fails at initialization.
Binary
Enabled
A column is null if it contains only the specified binary null character. The next column inherits the initial shift state of the code page.
Integration Service writes as many binary null characters as possible into the target field.
Non-binary
Enabled
A column is null if the repeating null character fits into the column exactly, with no bytes leftover. For example, a five-byte column is not null if you specify a two-byte repeating null character.
In shift-sensitive code pages, shift bytes do not affect the null value of a column. If a column contains a shift byte at the beginning or end of the column and the repeating null character fits into the column with no bytes left over, the column is null.
Specify a single-byte null character when you use repeating non-binary null characters. This ensures that repeating null characters fit into a column exactly.
Integration Service writes as many null characters as possible into the target field.
If you specify a multibyte null character and there are extra bytes left after writing the null characters, the Integration Service pads the column with single-byte spaces.
If a column is not big enough to take a null character because it is smaller than the multibyte character specified as the null character, the session fails at initialization.


Updated June 25, 2018