Query

Specialized has_any and has_all query lookups for flag enumerations.

class django_enum.query.HasAllFlagsLookup(*args, **kwargs)

Bases: Lookup

Query whether the left-hand side has all the bit flags on the right-hand side. This lookup bitwise ANDs the left-hand side with the right-hand side and checks that the result is equal to the right-hand side.

as_sql(compiler, connection)

Responsible for returning a (sql, [params]) tuple to be included in the current query.

Different backends can provide their own implementation, by providing an as_{vendor} method and patching the Expression:

``` def override_as_sql(self, compiler, connection):

# custom logic return super().as_sql(compiler, connection)

setattr(Expression, ‘as_’ + connection.vendor, override_as_sql) ```

Arguments:

• compiler: the query compiler responsible for generating the query. Must have a compile method, returning a (sql, [params]) tuple. Calling compiler(value) will return a quoted value.

• connection: the database connection used for the current query.

Return: (sql, params)

Where sql is a string containing ordered sql parameters to be replaced with the elements of the list params.

lookup_name = 'has_all'

class django_enum.query.HasAnyFlagsLookup(*args, **kwargs)

Bases: Lookup

Query whether the left-hand side has any of the bit flags on the right-hand side. This lookup bitwise ANDs the left-hand side with the right-hand side and checks that the result is not equal to zero.

as_sql(compiler, connection)

Responsible for returning a (sql, [params]) tuple to be included in the current query.

Different backends can provide their own implementation, by providing an as_{vendor} method and patching the Expression:

``` def override_as_sql(self, compiler, connection):

# custom logic return super().as_sql(compiler, connection)

setattr(Expression, ‘as_’ + connection.vendor, override_as_sql) ```

Arguments:

• compiler: the query compiler responsible for generating the query. Must have a compile method, returning a (sql, [params]) tuple. Calling compiler(value) will return a quoted value.

• connection: the database connection used for the current query.

Return: (sql, params)

Where sql is a string containing ordered sql parameters to be replaced with the elements of the list params.

lookup_name = 'has_any'