Module diesel::expression
source · Expand description
AST types representing various typed SQL expressions.
Almost all types implement either Expression
or
AsExpression
.
The most common expression to work with is a
Column
. There are various methods
that you can call on these, found in
expression_methods
.
You can also use numeric operators such as +
on expressions of the
appropriate type.
Any primitive which implements ToSql
will
also implement AsExpression
, allowing it to be
used as an argument to any of the methods described here.
Modules§
- array_
comparison i-implement-a-third-party-backend-and-opt-into-breaking-changes
This module contains the query dsl node definitions for array comparison operations likeIN
andNOT IN
- exists
i-implement-a-third-party-backend-and-opt-into-breaking-changes
This module contains the query dsl node definition forEXISTS
expressions - Possible types for []
Expression::SqlType
] - Helper macros to define custom sql functions
- Possible values for
ValidGrouping::IsAggregate
Structs§
- A SQL
CASE WHEN ... END
expression - Concat
i-implement-a-third-party-backend-and-opt-into-breaking-changes
This type represents a string concat operator - Returned by the
sql()
function. - Returned by the
SqlLiteral::bind()
method when binding a value to a fragment of SQL.
Traits§
- Indicates that all elements of an expression are valid given a from clause.
- Converts a type to its representation for use in Diesel’s query builder.
- Converts a tuple of values into a tuple of Diesel expressions.
- Helper trait used when boxing expressions.
- Represents a typed fragment of SQL.
- Converts a type to its representation for use in Diesel’s query builder.
- Can two
IsAggregate
types appear in the same expression? - NonAggregate
Non- unstable
Trait alias to represent an expression that isn’t aggregate by default. - A helper to translate type level sql type information into runtime type information for specific queries
- Trait indicating that a record can be selected and queried from the database.
- Indicates that an expression can be selected from a source.
- This helper trait provides several methods for constructing a select or returning clause based on a
Selectable
implementation. - Marker trait for possible types of
Expression::SqlType
- Is this expression valid for a given group by clause?
Derive Macros§
- Implements all required variants of
AsExpression
- Implements
Selectable
- Implements
ValidGrouping