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ASQN (Allow SQL Nulls) attribute
Specifying Conditions and Expressions in the Technical Reference Guide.
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If the target field does not have the ASQN attribute, the behavior varies depending on whether the *STRICT_NULL_ASSIGN function option is enabled. By default, the *NULL value for the field type will be assigned to the target field. In the example below, as #C is a numeric field, it would be set to zero. For a definition of what the *NULL value is for each of the field types refer to CHANGE Parameters.
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#C := #B |
However, if *STRICT_NULL_ASSIGN has been enabled, and the example code above is executed when #B is SQL Null, a fatal error will occur as the target field does not support being set to SQL Null. When working with *STRICT_NULL_ASSIGN, the LANSA Developer must code carefully to protect against such runtime errors. For example:
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If you wish to change the value of SQL Null fields to something more appropriate, use Intrinsic Method .AsValue. For example, the result of expression '#B.AsValue(1) + 1' is 2 when #B is SQL Null (and 5 when #B is 4).
SQL Null Handling
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