PEL advantages

  • Article

PerformancePoint Expression Language (PEL) has similarities to Multidimensional Expression (MDX) language and to SQL but it is not an extension of those languages.

PEL provides syntax and functionality that are optimized to create business rules in Planning Business Modeler. For example, PEL statements and commands enable you to do common business tasks, such as allocate resources or perform intercompany reconciliation. In addition, because business tasks depend on data retrieval, PEL supports definition and manipulation of multidimensional objects and data.

PEL is customized for the Planning Business Modeler environment. The PEL compiler generates complex SQL procedures or MDX queries for you. This enables you to spend less time with syntax and more time in rule design. In addition, the compiler automatically selects exactly the appropriate Planning Business Modeler component to process your calculations and it optimizes the whole process.

The following list describes important advantages to using PEL:

  • Conciseness

    Rules written in PEL are more concise than rules written in MDX or SQL. Compared with a PEL rule that performs the same task, a native SQL rule typically contains approximately ten times more code. Similarly, compared with a PEL rule that performs the same task, a rule written in MDX Query language contains three times more code. For example, a native SQL rule requires roughly 100 lines to perform the same task as 10 lines of PEL with an SQL implementation. This conciseness makes rules easier to write, easier to understand (especially for nonprogrammers), and easier to maintain. In particular, it is easy to change the implementation of a PEL rule from MDX to SQL or vice versa.

  • Superior error detection

    The PEL compiler can detect several error conditions at compile time. MDX detects similar errors at run time. This enables debugging and validation before a rule is integrated into a model and it helps make sure that rule users do not encounter problems.

  • Efficiency

    The PEL compiler applies several optimizations in the code that it generates.

  • Flexibility

    When you create business rules in PEL, Planning Business Modeler offers implementation options, data input options, and the ability to compare the results and performance of different implementations.

Limitations

The following list describes two scenarios for which it is better to write a rule in SQL or MDX than in PEL:

  • You might not be able to write your rule in PEL if the language does not support a construct that is available in native MDX or SQL. For example, the PEL compiler does not support the SQL implementation of many functions. For more information, see SQL generation for PEL functions.

  • PEL-generated MDX or SQL may run significantly slower than a corresponding native MDX or native SQL implementation. For example, the PEL compiler does not generate some MDX optimizations that can be employed in native MDX.

    If performance analysis shows that a PEL rule is running slowly, the rule author can use the Debug Rule dialog box to examine the generated MDX or SQL text. By analyzing the generated code, the rule author can determine whether an additional optimization can improve performance. For more information, see Debugging a rule.

See Also

Other Resources

About PerformancePoint Expression Language
PEL basics
Comparison of PEL to MDX