When caption text contains dtcorp20013 (ex : updtcorp2001340, jkuidtcorp20013ut), use the below mentioned query
SELECT NodeID, Caption FROM Orion.Nodes Where Caption like '%dtcorp20013%'
When caption text is dtcorp20013, use the equal to sign as provided below.
SELECT NodeID, Caption FROM Orion.Nodes Where Caption = 'dtcorp20013'
When ever you are comparing a text, it should be within single quotes ''.
You can find the documentation on SDK and the queries @ "C:\Program Files (x86)\SolarWinds\Orion SDK\Documentation"