Trait RowCount 

pub trait RowCount: Sealed {
    type Get<R>;

    // Required method
    fn first<R>(row: Option<R>) -> Result<Self::Get<R>, DrizzleError>;
}

How many rows a query returns, as far as its type knows: ExactlyOne or ZeroOrMore. It decides what .get() returns.

Required Associated Types

type Get<R>

What .get() returns for rows of type R.

Required Methods

fn first<R>(row: Option<R>) -> Result<Self::Get<R>, DrizzleError>

The first row of a result as Self::Get.

Errors

ExactlyOne returns DrizzleError::NotFound when the database returned no row.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl RowCount for ExactlyOne

type Get<R> = R

impl RowCount for ZeroOrMore

type Get<R> = Option<R>