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AI and Rules
If a query entity returns an empty set (due to the filters), will that empty set
Jason Ruvinsky
Certified Senior Developer
over 9 years ago
If a query entity returns an empty set (due to the filters), will that empty set be automatically cast to the type of the Data Entity, or do we need to perform this cast in our rules to ensure the query entity is null-safe (it always returns the expected type, whether it is an empty array or not. Otherwise using dot-notation to access fields of a CDT will result in errors, although the property() function would also let us be null-safe)....
OriginalPostID-131791
OriginalPostID-131791
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Jason Ruvinsky
Certified Senior Developer
over 9 years ago
Abhi, in my testing I've found that not to be the case. Yes, you can use dot notation to get the .data, but beyond that you can't necessarily treat the .data as the CDT type. You need to check if it is length()=0, and use cast(CDT_TYPE,{}) to create a valid empty CDT of the expected type to make it null-safe.
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Jason Ruvinsky
Certified Senior Developer
over 9 years ago
Abhi, in my testing I've found that not to be the case. Yes, you can use dot notation to get the .data, but beyond that you can't necessarily treat the .data as the CDT type. You need to check if it is length()=0, and use cast(CDT_TYPE,{}) to create a valid empty CDT of the expected type to make it null-safe.
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