Check if a node is a primary key
Verified
Added by iNTERFACEWARE
Use node.isKey() to check if a node is the primary key for a database table, this method only for table node trees
Source Code
-- create a tables node tree to use local Out = db.tables{vmd = 'example/demo.vmd', name = Name} -- test if the "Id" field is the Primary Key for patient local iskey = Out.patient[1].Id:isKey() --> true -- test if the "PatientId" field is the Primary Key for kin local iskey = Out.kin[1].PatientId:isKey() --> false
Description
Use node.isKey() to check if a node is the primary key for a database table, this method only for table node trees
Usage Details
Use node.isKey()
to check if a node is the primary key for a database table.
Note: The node.isKey()
function only works with table node trees.
How to use the snippet:
- Paste the code into your script
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