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Tech Tip: Checking if an Object Field is NULL with the NULL command vs. Is field value Null
PRODUCT: 4D | VERSION: 17 | PLATFORM: Mac & Win
Published On: October 8, 2018
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Prior to v17, checking if a field value is NULL can be done with Is field value Null command. This verification is done with the 4D SQL engine. The limitation of this command is that Object field is not supported with 4D SQL engine. But in v17, an Object field can be checked with the NULL command. Here is an example:

If ([Table_1]Field_obj=Null)
  // True if it is NULL
End if


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