Trait Entity 

pub trait Entity {
    type PrimaryKey<'a>;

    // Required methods
    fn table() -> &'static TableRef;
    fn columns() -> &'static [ColumnDef];
    fn primary_key_def() -> &'static [&'static ColumnDef];
    fn primary_key(&self) -> Self::PrimaryKey<'_>;
    fn unique_defs(    ) -> impl ExactSizeIterator<Item = impl ExactSizeIterator<Item = &'static ColumnDef>>;
    fn row_filtered(&self) -> Box<[(&'static str, Value)]>;
    fn row_full(&self) -> Row;
    fn from_row(row: RowLabeled) -> Result<Self>
       where Self: Sized;
    fn find_pk(
        executor: &mut impl Executor,
        primary_key: &Self::PrimaryKey<'_>,
    ) -> impl Future<Output = Result<Option<Self>>> + Send
       where Self: Sized;
    fn delete_one(
        executor: &mut impl Executor,
        primary_key: Self::PrimaryKey<'_>,
    ) -> impl Future<Output = Result<RowsAffected>> + Send
       where Self: Sized;

    // Provided methods
    fn create_table(
        executor: &mut impl Executor,
        if_not_exists: bool,
        create_schema: bool,
    ) -> impl Future<Output = Result<()>> + Send
       where Self: Sized { ... }
    fn drop_table(
        executor: &mut impl Executor,
        if_exists: bool,
        drop_schema: bool,
    ) -> impl Future<Output = Result<()>> + Send
       where Self: Sized { ... }
    fn insert_one(
        executor: &mut impl Executor,
        entity: &impl Entity,
    ) -> impl Future<Output = Result<RowsAffected>> + Send { ... }
    fn insert_many<'a, It>(
        executor: &mut impl Executor,
        items: It,
    ) -> impl Future<Output = Result<RowsAffected>> + Send
       where Self: 'a + Sized,
             It: IntoIterator<Item = &'a Self> + Send,
             <It as IntoIterator>::IntoIter: Send { ... }
    fn prepare_find<Exec: Executor>(
        executor: &mut Exec,
        condition: &impl Expression,
        limit: Option<u32>,
    ) -> impl Future<Output = Result<Query<Exec::Driver>>> { ... }
    fn find_one(
        executor: &mut impl Executor,
        condition: &impl Expression,
    ) -> impl Future<Output = Result<Option<Self>>> + Send
       where Self: Sized { ... }
    fn find_many(
        executor: &mut impl Executor,
        condition: impl Expression,
        limit: Option<u32>,
    ) -> impl Stream<Item = Result<Self>> + Send
       where Self: Sized { ... }
    fn delete_many(
        executor: &mut impl Executor,
        condition: &impl Expression,
    ) -> impl Future<Output = Result<RowsAffected>> + Send
       where Self: Sized { ... }
    fn save(
        &self,
        executor: &mut impl Executor,
    ) -> impl Future<Output = Result<()>> + Send
       where Self: Sized { ... }
    fn delete(
        &self,
        executor: &mut impl Executor,
    ) -> impl Future<Output = Result<()>> + Send
       where Self: Sized { ... }
}

A table-mapped record with schema and CRUD helpers.

Required Associated Types

type PrimaryKey<'a>

Primary key type. Tuple of the types of the fields forming the primary key.

Required Methods

fn table() -> &'static TableRef

Returns the table reference backing this entity.

fn columns() -> &'static [ColumnDef]

Returns all declared column definitions in declaration order.

fn primary_key_def() -> &'static [&'static ColumnDef]

Iterator over columns forming the primary key. Empty iterator means no PK.

fn primary_key(&self) -> Self::PrimaryKey<'_>

Extracts the primary key value(s) from self.

fn unique_defs() -> impl ExactSizeIterator<Item = impl ExactSizeIterator<Item = &'static ColumnDef>>

Returns an iterator over unique constraint definitions.

fn row_filtered(&self) -> Box<[(&'static str, Value)]>

Returns a filtered mapping of column name to value, typically excluding auto-generated or default-only columns.

fn row_full(&self) -> Row

Returns a full Row representation including all persisted columns.

fn from_row(row: RowLabeled) -> Result<Self>

where Self: Sized,

Constructs Self from a labeled database row.

Error if mandatory columns are missing or type conversion fails.

fn find_pk( executor: &mut impl Executor, primary_key: &Self::PrimaryKey<'_>, ) -> impl Future<Output = Result<Option<Self>>> + Send

where Self: Sized,

Finds an entity by primary key.

Returns Ok(None) if no row matches.

fn delete_one( executor: &mut impl Executor, primary_key: Self::PrimaryKey<'_>, ) -> impl Future<Output = Result<RowsAffected>> + Send

where Self: Sized,

Deletes exactly one entity by primary key.

Returns rows affected (0 if not found).

Provided Methods

fn create_table( executor: &mut impl Executor, if_not_exists: bool, create_schema: bool, ) -> impl Future<Output = Result<()>> + Send

where Self: Sized,

Creates the underlying table (and optionally schema) if requested.

Parameters:

• if_not_exists: guards against existing table (if drivers support it, otherwise just create table).
• create_schema: attempt to create schema prior to table creation (if drivers support it).

fn drop_table( executor: &mut impl Executor, if_exists: bool, drop_schema: bool, ) -> impl Future<Output = Result<()>> + Send

where Self: Sized,

Drops the underlying table (and optionally schema) if requested.

Parameters:

• if_exists: guards against missing table (if drivers support it, otherwise just drop table).
• drop_schema: attempt to drop schema after table removal (if drivers support it).

fn insert_one( executor: &mut impl Executor, entity: &impl Entity, ) -> impl Future<Output = Result<RowsAffected>> + Send

Inserts a single entity row.

Returns rows affected (expected: 1 on success).

fn insert_many<'a, It>( executor: &mut impl Executor, items: It, ) -> impl Future<Output = Result<RowsAffected>> + Send

where Self: 'a + Sized, It: IntoIterator<Item = &'a Self> + Send, <It as IntoIterator>::IntoIter: Send,

Multiple insert for a homogeneous iterator of entities.

Returns the number of rows inserted.

fn prepare_find<Exec: Executor>( executor: &mut Exec, condition: &impl Expression, limit: Option<u32>, ) -> impl Future<Output = Result<Query<Exec::Driver>>>

Prepare (but do not yet run) a SQL select query.

Returns the prepared statement.

fn find_one( executor: &mut impl Executor, condition: &impl Expression, ) -> impl Future<Output = Result<Option<Self>>> + Send

where Self: Sized,

Finds the first entity matching a condition expression.

Returns Ok(None) if no row matches.

fn find_many( executor: &mut impl Executor, condition: impl Expression, limit: Option<u32>, ) -> impl Stream<Item = Result<Self>> + Send

where Self: Sized,

Streams entities matching a condition.

limit restricts the maximum number of rows returned at a database level if Some (if supported by the driver, unlimited otherwise).

fn delete_many( executor: &mut impl Executor, condition: &impl Expression, ) -> impl Future<Output = Result<RowsAffected>> + Send

where Self: Sized,

Deletes all entities matching a condition.

Returns the number of rows deleted.

fn save( &self, executor: &mut impl Executor, ) -> impl Future<Output = Result<()>> + Send

where Self: Sized,

Saves the entity (insert or update if available) based on primary key presence.

Errors:

• Missing PK in the table.
• Execution failures from underlying driver.

fn delete( &self, executor: &mut impl Executor, ) -> impl Future<Output = Result<()>> + Send

where Self: Sized,

Deletes this entity instance via its primary key.

Errors:

• Missing PK in the table.
• If not exactly one row was deleted.
• Execution failures from underlying driver.

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