Transform distributed data values - Connect_CDC - connect_cdc_mimix_share - 5 - 5.8

Connect CDC Advanced User Guide

Product type
Product family
Connect > Connect CDC (MIMIX Share)
Product name
Connect CDC
Connect CDC Advanced User Guide
First publish date

Connect CDC has options that let you modify the source data you are distributing or even create or derive the data you distribute. You can use predefined functions to accomplish these data transformations or you can construct your own operations or functions.

For example, to express source currency values in terms of a different currency, you specify the transformation algorithm to use for that column mapping. For some common transformations, the algorithm is supplied as a predefined Connect CDC function.

The algorithms you specify are known in the Connect CDC Director as expressions. The Connect CDC Expression Handler parses them and then creates runtime code that calculates the result for the expressions.

In addition to or instead of calls to predefined functions, expressions may have an arbitrary number of constants, column references, and calculations on those constants and columns and functions. Their results must be compatible in type and length with the target column.

The example that follows demonstrates a simple expression, that is, an expression that operates on named source columns without programming statements to produce a value to send to the target column. In contrast, a complex expression is like a procedure in that it always returns a value, may have a programming statement, and always consists of more than one line. You can also can define named complex expressions, which you can reference in other expressions.

The System Reference provides the Expression Handler details. The Expression Handler rules, including its valid operators (arithmetic, comparison, and Boolean) and statements are a combination of SQL and Java symbols and conventions.

Note: For expressions to compile correctly, the computer’s PATH must contain the directory for the java.exe and javac.exe file. An example of such a PATH follows, where the referenced directory is in bold.
            %SystemRoot%\System32\Wbem;C:\Program Files\Microsoft SQL Server

To check the computer’s path, do the following:

  1. Right-click My Computer, the select Properties in the menu that displays.

  2. Click the Advanced tab, then click the Environment Variables button.

  3. In System variables, select Path, then click Edit.

  4. In Variable Value, check for the correct directory.