mysql sqlalchemy 索引_SQLAlchemy中指定想要使用的索引

我们知道在MySQL中可以使用FORCE INDEX(index_name,...)来强制使用索引，那在SQLAlchemy如何指定呢？

经过多方查找和实践，我发现了一个叫with_hint的函数。

我们看下源码

def with_hint(self, selectable, text, dialect_name="*"):

r"""Add an indexing or other executional context hint for the given

selectable to this :class:`.Select`.

The text of the hint is rendered in the appropriate

location for the database backend in use, relative

to the given :class:`.Table` or :class:`.Alias` passed as the

``selectable`` argument. The dialect implementation

typically uses Python string substitution syntax

with the token ``%(name)s`` to render the name of

the table or alias. E.g. when using Oracle, the

following::

select([mytable]).\

with_hint(mytable, "index(%(name)s ix_mytable)")