Trait FromColumn 

pub trait FromColumn: Sized {
    // Required method
    fn from_column(row: &dyn Row, col: &str) -> Result<Self>;
}

Decodes one column of a Row into a Rust value. The generated decoder calls T::from_column(row, "col")? per field. The bare T impls treat a NULL as a decode error; the blanket Option<T> impl below turns it into None.

Required Methods

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

Dyn Compatibility

This trait is not dyn compatible.

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

Implementations on Foreign Types

impl FromColumn for DateTime<Utc>

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl FromColumn for NaiveDate

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl FromColumn for String

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl FromColumn for Vec<u8>

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl FromColumn for bool

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl FromColumn for f64

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl FromColumn for i32

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl FromColumn for i64

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl FromColumn for u32

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl FromColumn for u64

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

impl<T: FromColumn + SqlType> FromColumn for Option<T>

Blanket nullability: any decodable, typed column is decodable as Option. Living in this crate (not a per-type macro) keeps it coherent — a custom type gets Option support for free from its bare FromColumn + SqlType, without a downstream impl … for Option<Custom> (which the orphan rule forbids). Presence is probed through the getter matching the type’s ColumnType; only a present cell is decoded.

fn from_column(row: &dyn Row, col: &str) -> Result<Self>

Implementors

impl FromColumn for Base64Bytes

impl FromColumn for ShardStatus

impl<T: DeserializeOwned> FromColumn for Json<T>