Function exp 

pub fn exp<'a, V, E>(
    expr: E,
) -> SQLExpr<'a, V, <V::DialectMarker as DialectTypes>::Double, E::Nullable, E::Aggregate>
where
    V: SQLParam + 'a,
    E: Expr<'a, V>,
    E::SQLType: Numeric,

EXP - returns e raised to the power of the argument.

Returns a dialect-aware double type, preserves nullability.

Example

use drizzle_core::expr::exp;

// SELECT EXP(users.rate)
let exponential = exp(users.rate);