Function seed_sql 

pub fn seed_sql(
    rel: &str,
    dim_cols: &[String],
    value_col: &str,
    agg: Agg,
) -> String

The SELECT that loads an agg binding’s fold state for Mapper::seed: per coordinate (dimension columns as text, rel already quoted), the value text the fold keeps, count(value_col) and count(*) (FoldRow), then a NULL. For count no value; for sum and avg the finite values’ sum and, in groups of their own, the infinities and NaNs; for min, max and count_distinct one group per value text. One more row has NULL dimensions and, last, the statement’s snapshot.