long_sequence(iterations)- generates rows
long_sequence(iterations, seed1, seed2)- generates rows deterministically
iterations: is a
long representing the number of rows to generate. -
long64 representing both parts of a
long_sequence(iterations) is used to:
- Generate a number of rows defined by
- Generate a column
x:longof monotonically increasing long integers starting from 1, which can be accessed for queries.
You can use this to generate very large datasets for your testing e.g billions of rows or more if your disk allows.
Random number seed
long_sequence is used conjointly with
random generators, these values
are usually generated at random. The function supports a seed to be passed in
order to produce deterministic results.
Deterministic procedural generation makes it easy to test on vasts amounts of data without actually moving large files around across machines. Using the same seed on any machine at any time will consistently produce the same results for all random functions.
The results below will be the same on any machine at any time as long as they use the same seed in long_sequence.