Mapping string functions: BasicStringFuncMapper element

The BasicStringFuncMapper element is used for customizing the mappings of the functions listed in Table 11-7. The table also shows the default template for each function.

Table 11-7

Default templates for mapping string functions

String function	Operand data types	Default template
CHAR_LENGTH	<VARCHAR>, <INTEGER>	{FN LENGTH ($P0)}
UPPER	<VARCHAR>	{FN UCASE ($P0)}
LOWER	<VARCHAR>	{FN LCASE ($P0)}
LTRIM	<VARCHAR>	{FN LTRIM ($P0)}
RTRIM	<VARCHAR>	{FN RTRIM ($P0)}
CONCAT	<VARCHAR>, <VARCHAR>	{FN CONCAT ($P0, $P1)}

Example: Mapping the CHAR_LENGTH function

The Actuate SQL CHAR_LENGTH function returns the length of a string including trailing spaces. The corresponding database function, however, ignores trailing spaces. To resolve this discrepancy, the following mapping appends an underscore (_) to the string, applies the database function LEN, and subtracts one:

<BasicStringFuncMapper>

  <FunctionMappings>

    <FunctionMapping FunctionName="CHAR_LENGTH">

      LEN ($P0 + '_') - 1

    </FunctionMapping>

  </FunctionMappings>

</BasicStringFuncMapper>

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