Function sample_rows 

pub fn sample_rows(
    percent: f32,
    seed: Option<f64>,
    count: usize,
    session: &dyn Session,
) -> Result<Vec<usize>>

BeginSampleScan of the two methods and the choice of the rows: the numbers of the rows, of count, that the sample keeps. seed is the value of REPEATABLE. With None, the seed comes from pg_global_prng_state, as in tablesample_init.

Errors

2202H when the percentage is not between 0 and 100.