Module diesel::prelude [−] [src]

Re-exports important traits and types. Meant to be glob imported when using Diesel.

Reexports

pub use connection::Connection;

pub use expression::{Expression, SelectableExpression, BoxableExpression};

pub use expression::expression_methods::*;

pub use query_source::{QuerySource, Queryable, Table, Column};

pub use result::{QueryResult, TransactionError, TransactionResult, ConnectionError, ConnectionResult, OptionalExtension};

Traits

BelongingToDsl
BoxedDsl	Boxes the pieces of a query into a single type. This is useful for cases where you want to conditionally modify a query, but need the type to remain the same. The backend must be specified as part of this. It is not possible to box a query and have it be useable on multiple backends.
CountDsl	Adds a simple `count` function to queries. Automatically implemented for all types which implement `SelectDsl`.
DistinctDsl	Adds the `DISTINCT` keyword to a query.
ExecuteDsl
FilterDsl	Adds to the `WHERE` clause of a query. If there is already a `WHERE` clause, the result will be `old AND new`. This is automatically implemented for the various query builder types.
FindDsl	Attempts to find a single record from the given table by primary key.
GroupedBy
Insertable	Represents that a structure can be used to to insert a new row into the database. This is automatically implemented for `&[T]` and `&Vec<T>` for inserting more than one record.
JoinTo	Indicates that two tables can be used together in a JOIN clause. Implementations of this trait will be generated for you automatically by the association annotations from codegen.
LimitDsl	Sets the limit clause of a query. If there was already a limit clause, it will be overridden. This is automatically implemented for the various query builder types.
LoadDsl	Methods to execute a query given a connection. These are automatically implemented for the various query types.
OffsetDsl	Sets the offset clause of a query. If there was already a offset clause, it will be overridden. This is automatically implemented for the various query builder types.
OrderDsl	Sets the order clause of a query. If there was already a order clause, it will be overridden. The expression passed to `order` must actually be valid for the query. See also: `.desc()` and `.asc()`
SaveChangesDsl
SelectDsl	Sets the select clause of a query. If there was already a select clause, it will be overridden. The expression passed to `select` must actually be valid for the query (only contains columns from the target table, doesn't mix aggregate + non-aggregate expressions, etc).
WithDsl	Adds an additional expression to the FROM clause. This is useful for things like full text search, where you need to access the result of an expensive computation for the where clause that shouldn't be redone for each row, such as `plain_to_tsquery`. See `.aliased` for more