Trait QueryEngine 

pub trait QueryEngine:
    Send
    + Sync
    + Clone
    + 'static {
    // Required methods
    fn query_many<T: Model + Send + 'static>(
        &self,
        sql: &str,
        params: Vec<FilterValue>,
    ) -> BoxFuture<'_, QueryResult<Vec<T>>>;
    fn query_one<T: Model + Send + 'static>(
        &self,
        sql: &str,
        params: Vec<FilterValue>,
    ) -> BoxFuture<'_, QueryResult<T>>;
    fn query_optional<T: Model + Send + 'static>(
        &self,
        sql: &str,
        params: Vec<FilterValue>,
    ) -> BoxFuture<'_, QueryResult<Option<T>>>;
    fn execute_insert<T: Model + Send + 'static>(
        &self,
        sql: &str,
        params: Vec<FilterValue>,
    ) -> BoxFuture<'_, QueryResult<T>>;
    fn execute_update<T: Model + Send + 'static>(
        &self,
        sql: &str,
        params: Vec<FilterValue>,
    ) -> BoxFuture<'_, QueryResult<Vec<T>>>;
    fn execute_delete(
        &self,
        sql: &str,
        params: Vec<FilterValue>,
    ) -> BoxFuture<'_, QueryResult<u64>>;
    fn execute_raw(
        &self,
        sql: &str,
        params: Vec<FilterValue>,
    ) -> BoxFuture<'_, QueryResult<u64>>;
    fn count(
        &self,
        sql: &str,
        params: Vec<FilterValue>,
    ) -> BoxFuture<'_, QueryResult<u64>>;

    // Provided method
    fn refresh_materialized_view(
        &self,
        view_name: &str,
        concurrently: bool,
    ) -> BoxFuture<'_, QueryResult<()>> { ... }
}

The query engine abstraction.

This trait defines how queries are executed against a database. Different implementations can be provided for different databases (PostgreSQL, MySQL, SQLite, etc.).

Required Methods

fn query_many<T: Model + Send + 'static>( &self, sql: &str, params: Vec<FilterValue>, ) -> BoxFuture<'_, QueryResult<Vec<T>>>

Execute a SELECT query and return rows.

fn query_one<T: Model + Send + 'static>( &self, sql: &str, params: Vec<FilterValue>, ) -> BoxFuture<'_, QueryResult<T>>

Execute a SELECT query expecting one result.

fn query_optional<T: Model + Send + 'static>( &self, sql: &str, params: Vec<FilterValue>, ) -> BoxFuture<'_, QueryResult<Option<T>>>

Execute a SELECT query expecting zero or one result.

fn execute_insert<T: Model + Send + 'static>( &self, sql: &str, params: Vec<FilterValue>, ) -> BoxFuture<'_, QueryResult<T>>

Execute an INSERT query and return the created row.

fn execute_update<T: Model + Send + 'static>( &self, sql: &str, params: Vec<FilterValue>, ) -> BoxFuture<'_, QueryResult<Vec<T>>>

Execute an UPDATE query and return affected rows.

fn execute_delete( &self, sql: &str, params: Vec<FilterValue>, ) -> BoxFuture<'_, QueryResult<u64>>

Execute a DELETE query and return affected rows count.

fn execute_raw( &self, sql: &str, params: Vec<FilterValue>, ) -> BoxFuture<'_, QueryResult<u64>>

Execute a raw SQL query.

fn count( &self, sql: &str, params: Vec<FilterValue>, ) -> BoxFuture<'_, QueryResult<u64>>

Get a count of records.

Provided Methods

fn refresh_materialized_view( &self, view_name: &str, concurrently: bool, ) -> BoxFuture<'_, QueryResult<()>>

Refresh a materialized view.

For PostgreSQL, this executes REFRESH MATERIALIZED VIEW. For MSSQL, this rebuilds the indexed view. For databases that don’t support materialized views, this returns an error.

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