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Update the name of the latest til

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jbranchaud
2016-02-03 19:47:31 -06:00
parent 19a973e780
commit a9ae2fab69
2 changed files with 2 additions and 2 deletions

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# Set A Seed For The Random Number Generator
In PostgreSQL, the internal seed for the random number generator is a
run-time configuration parameter. This `seed` parameter can be set to a
particular seed in order to get some determinism from functions that utilize
the random number generator. The seed needs to be something between `0` and
`1`.
We can see this in action by setting the seed and then invoking `random()` a
couple times. Doing this twice, we will see the reproducibility we can
achieve with a seed.
```sql
> set seed to 0.1234;
SET
> select random();
random
-------------------
0.397731185890734
> select random();
random
------------------
0.39575699577108
(1 row)
> set seed to 0.1234;
SET
> select random();
random
-------------------
0.397731185890734
> select random();
random
------------------
0.39575699577108
```
The seed can also be configured with the `setseed()` function.
See [the PostgreSQL
docs](http://www.postgresql.org/docs/8.3/static/sql-set.html) for more
details.