random_normal()
A function providing normally-distributed random numbers
random_normal() is a system function providing normally-distributed random numbers.
random_normal() was added in PostgreSQL 16.
Usage
random_normal ( [meandouble precision[,stddevdouble precision]] ) →double precision
random_normal() produces a set of normally distributed random values using Gaussian distribution.
mean speciieds the mean of the normal distribution of values. stddev is the standard deviation of the normal distribution of values.
A function with similar functionality, normal_rand(), is available via the tablefunc contrib module.
Change history
- PostgreSQL 16
- added (commit 38d81760)
Examples
Basic usage example for random_normal():
postgres=# SELECT random_normal(); random_normal -------------------- 0.7821236960137614 (1 row)
Providing a mean value:
postgres=# SELECT random_normal(5) from generate_series(1,5); random_normal ------------------- 5.29703419771379 3.623749811810435 6.572131718905143 4.428844367745707 6.250520372123069 (5 rows)
References
- PostgreSQL 16 documentation: Random Functions
Useful links
- Waiting for PostgreSQL 16 – Invent random_normal() to provide normally-distributed random numbers - January 2023 blog article by Hubert 'depesz' Lubaczewski
