Struct NoFromClause

pub struct NoFromClause;

This type represents a not existing from clause

Custom backends can provide a custom QueryFragment impl by specializing the implementation via SqlDialect::EmptyFromClauseSyntax

Trait Implementations

impl Clone for NoFromClause

fn clone(&self) -> NoFromClause

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for NoFromClause

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<DB> QueryFragment<DB> for NoFromClause

where Self: QueryFragment<DB, DB::EmptyFromClauseSyntax>, DB: Backend,

fn walk_ast<'b>(&'b self, pass: AstPass<'_, 'b, DB>) -> QueryResult<()>

Walk over this QueryFragment for all passes.

fn to_sql(&self, out: &mut DB::QueryBuilder, backend: &DB) -> QueryResult<()>

Converts this QueryFragment to its SQL representation.

fn collect_binds<'b>( &'b self, out: &mut DB::BindCollector<'b>, metadata_lookup: &mut DB::MetadataLookup, backend: &'b DB, ) -> QueryResult<()>

Serializes all bind parameters in this query.

fn is_safe_to_cache_prepared(&self, backend: &DB) -> QueryResult<bool>

Is this query safe to store in the prepared statement cache?

fn is_noop(&self, backend: &DB) -> QueryResult<bool>

Does walking this AST have any effect?

impl<DB> QueryFragment<DB, AnsiSqlFromClauseSyntax> for NoFromClause

where DB: Backend<EmptyFromClauseSyntax = AnsiSqlFromClauseSyntax>,

fn walk_ast<'b>(&'b self, _pass: AstPass<'_, 'b, DB>) -> QueryResult<()>

Walk over this QueryFragment for all passes.

fn to_sql(&self, out: &mut DB::QueryBuilder, backend: &DB) -> QueryResult<()>

Converts this QueryFragment to its SQL representation.

fn collect_binds<'b>( &'b self, out: &mut DB::BindCollector<'b>, metadata_lookup: &mut DB::MetadataLookup, backend: &'b DB, ) -> QueryResult<()>

Serializes all bind parameters in this query.

fn is_safe_to_cache_prepared(&self, backend: &DB) -> QueryResult<bool>

Is this query safe to store in the prepared statement cache?

fn is_noop(&self, backend: &DB) -> QueryResult<bool>

Does walking this AST have any effect?

impl QueryId for NoFromClause

const HAS_STATIC_QUERY_ID: bool = true

Can the SQL generated by Self be uniquely identified by its type?

type QueryId = NoFromClause

A type which uniquely represents Self in a SQL query.

fn query_id() -> Option<TypeId>

Returns the type id of Self::QueryId if Self::HAS_STATIC_QUERY_ID. Returns None otherwise.

impl Copy for NoFromClause