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CURRENT_USER (Transact-SQL)
Returns the name of the current user. This function is equivalent to USER_NAME().
When I execute the two function with the following TSQL scripts (the questionable ones were commented), I'm confused about the invocation syntax. I want to know when to use the parenthesis and when not. Thanks!
SELECT CURRENT_USER
-- SELECT CURRENT_USER() -- Error!
SELECT USER_NAME()
-- SELECT USER_NAME -- Error!