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ABENSQL_CASE_SEQUENCE - SQL CASE SEQUENCE

• The SQL standard specifies the result of a case distinction, but not the order in which the operands are evaluated. Potentially, the result may even be evaluated before the associated condition. This means that any expressions specified as operands must have no side effects and must not be dependent on each other.

• On the SAP HANA database, operands are evaluated in parallel for reasons of optimization. The order in which the operands are evaluated is undefined. If an exception is raised when an operand is evaluated, the entire case distinction is canceled. In this case, it does not matter which conditions apply and the order in which they are listed. For this reason, it is advisable not to use any exceptions in expressions specified as operands. For more information, see the HANA-specific SQL documentation.