from django.db.models.sql import compiler class SQLCompiler(compiler.SQLCompiler): def as_subquery_condition(self, alias, columns, compiler): qn = compiler.quote_name_unless_alias qn2 = self.connection.ops.quote_name sql, params = self.as_sql() return '(%s) IN (%s)' % (', '.join('%s.%s' % (qn(alias), qn2(column)) for column in columns), sql), params class SQLInsertCompiler(compiler.SQLInsertCompiler, SQLCompiler): pass class SQLDeleteCompiler(compiler.SQLDeleteCompiler, SQLCompiler): def as_sql(self): if self.connection.features.update_can_self_select or self.single_alias: return super().as_sql() # MySQL and MariaDB < 10.3.2 doesn't support deletion with a subquery # which is what the default implementation of SQLDeleteCompiler uses # when multiple tables are involved. Use the MySQL/MariaDB specific # DELETE table FROM table syntax instead to avoid performing the # operation in two queries. result = [ 'DELETE %s FROM' % self.quote_name_unless_alias( self.query.get_initial_alias() ) ] from_sql, from_params = self.get_from_clause() result.extend(from_sql) where, params = self.compile(self.query.where) if where: result.append('WHERE %s' % where) return ' '.join(result), tuple(from_params) + tuple(params) class SQLUpdateCompiler(compiler.SQLUpdateCompiler, SQLCompiler): pass class SQLAggregateCompiler(compiler.SQLAggregateCompiler, SQLCompiler): pass