base.py 文件源码

def visit_typeclause(self, typeclause, type_=None):
        if type_ is None:
            type_ = typeclause.type.dialect_impl(self.dialect)
        if isinstance(type_, sqltypes.TypeDecorator):
            return self.visit_typeclause(typeclause, type_.impl)
        elif isinstance(type_, sqltypes.Integer):
            if getattr(type_, 'unsigned', False):
                return 'UNSIGNED INTEGER'
            else:
                return 'SIGNED INTEGER'
        elif isinstance(type_, sqltypes.TIMESTAMP):
            return 'DATETIME'
        elif isinstance(type_, (sqltypes.DECIMAL, sqltypes.DateTime,
                                sqltypes.Date, sqltypes.Time)):
            return self.dialect.type_compiler.process(type_)
        elif isinstance(type_, sqltypes.String) \
                and not isinstance(type_, (ENUM, SET)):
            adapted = CHAR._adapt_string_for_cast(type_)
            return self.dialect.type_compiler.process(adapted)
        elif isinstance(type_, sqltypes._Binary):
            return 'BINARY'
        elif isinstance(type_, sqltypes.JSON):
            return "JSON"
        elif isinstance(type_, sqltypes.NUMERIC):
            return self.dialect.type_compiler.process(
                type_).replace('NUMERIC', 'DECIMAL')
        else:
            return None