Deterministic and Nondeterministic Functions:
Deterministic functions always return the same result any time they are called with a specific set of input values and given the same state of the database.
Examples: Sum(), AVG(), Square(), Power() and Count()
Note: All aggregate functions are deterministic functions.
Nondeterministic functions may return different results each time they are called with a specific set of input values even if the database state that they access remains the same.
Examples: GetDate() and CURRENT_TIMESTAMP
Rand() function is a Non-deterministic function, but if you provide the seed value, the function becomes deterministic, as the same value gets returned for the same seed value.
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