Trait ValueRef

pub trait ValueRef<'r>: Sized {
    type Database: Database;

    // Required methods
    fn to_owned(&self) -> <Self::Database as Database>::Value;
    fn type_info(&self) -> Cow<'_, <Self::Database as Database>::TypeInfo>;
    fn is_null(&self) -> bool;
}

A reference to a single value from the database.

Required Associated Types

type Database: Database

Required Methods

fn to_owned(&self) -> <Self::Database as Database>::Value

Creates an owned value from this value reference.

This is just a reference increment in PostgreSQL and MySQL and thus is O(1). In SQLite, this is a copy.

fn type_info(&self) -> Cow<'_, <Self::Database as Database>::TypeInfo>

Get the type information for this value.

fn is_null(&self) -> bool

Returns true if the SQL value is NULL.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl ValueRef<'_> for MssqlValueRef<'_>

Available on crate feature mssql only.

type Database = Mssql

impl<'r> ValueRef<'r> for AnyValueRef<'r>

type Database = Any

impl<'r> ValueRef<'r> for MySqlValueRef<'r>

Available on crate feature mysql only.

type Database = MySql

impl<'r> ValueRef<'r> for PgValueRef<'r>

Available on crate feature postgres only.

type Database = Postgres

impl<'r> ValueRef<'r> for SqliteValueRef<'r>

Available on crate feature sqlite only.

type Database = Sqlite