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• NULL and special values:
A standard query on a parameter will not return granules with NULL/void value. E.g. target_name LIKE '%toto%' will only select granules with this value (standard ADQL behavior).
NULL/void has to be tested specifically (e.g., when it means "I don't know") using the IS operator (IS is used only to test the NULL value in ADQL):
target_name LIKE '%toto%' OR target_name is name IS NULL
Operator Syntax IS also NULL stands for both strings and numerical parameters (the = operator is accepted in this context only by latest DaCHS servers only)
No inf, - inf, or NaN value in ADQL? Should At least Inf/-Inf should be there, as per DALI.
• UCDs: the above table has been reviewed against the UCD documents, including latest discussions (4/2019). Review against PDS4 and IPDA to be performed.
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