blocks|key|59657|text|有几个相关的问题，但我没有看到任何完全相同的副本。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|59658|使用您的代码获取表名，使用this+question接受的答案获取类，我们可以将类与数据库中注册的表名进行匹配。|offset|length|59659|classes,+models,+table_names+=+[],+[],+[]
for+clazz+in+db.Model._decl_class_registry.values():
++++try:
++++++++table_names.append(clazz.__tablename__)
++++++++classes.append(clazz)
++++except:
++++++++pass
for+table+in+db.metadata.tables.items():
++++if+table[0]+in+table_names:
++++++++models.append(classes[table_names.index(table[0])])|code-block|syntax|javascript|59660|其中，models是在数据库中注册的型号列表。|style|CODE|59661|try+catch是必需的，因为<sqlalchemy.ext.declarative.clsregistry._ModuleMarker+object>将包含在for+clazz+in+...循环中，而它没有__tablename__属性。|59662|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/11668355/sqlalchemy-get-model-from-table-name-this-may-imply-appending-some-function-to^0|0|D|D|0|0|0|3|6|0|G|1P|29|G|2X|D|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Z|8|@]|9|@$D|10|E|11|1|12]]|A|$]]|$1|F|3|G|5|H|7|13|8|@]|9|@]|A|$I|J]]|$1|K|3|L|5|6|7|14|8|@$D|15|E|16|M|N]]|9|@]|A|$]]|$1|O|3|P|5|6|7|17|8|@$D|18|E|19|M|N]|$D|1A|E|1B|M|N]|$D|1C|E|1D|M|N]]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|1E|8|@]|9|@]|A|$]]]|R|$S|$5|T|U|V|A|$W|X]]]]

There are several related questions, but I didn't see any exact duplicates.

Using your code to get the table names, and <a href="https://stackoverflow.com/questions/11668355/sqlalchemy-get-model-from-table-name-this-may-imply-appending-some-function-to">this question</a>'s accepted answer to get the classes, we can match the classes to the tablenames that are registered on your database.

<pre><code>classes, models, table_names = [], [], []
for clazz in db.Model._decl_class_registry.values():
 try:
 table_names.append(clazz.__tablename__)
 classes.append(clazz)
 except:
 pass
for table in db.metadata.tables.items():
 if table[0] in table_names:
 models.append(classes[table_names.index(table[0])])
</code></pre>

Where <code>models</code> is the list of models registed on your database.

The try catch is required because a <code>&lt;sqlalchemy.ext.declarative.clsregistry._ModuleMarker object&gt;</code> will be included in the <code>for clazz in ...</code> loop, and it doesn't have a <code>__tablename__</code> attribute.

blocks|key|59700|text|这在我的例子中是可行的:略短一些；更易读|type|unstyled|depth|inlineStyleRanges|entityRanges|data|59701|models+=+[]
for+name,+thing+in+db_table_creation.__dict__.iteritems():
++++if+isinstance(thing,+sqlalchemy.ext.declarative.DeclarativeMeta)+and+hasattr(thing,+'__tablename__'):
++++++++models.append(thing)|code-block|syntax|javascript|59702|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

this works in my case: slightly shorter; more readable

<pre><code>models = []
for name, thing in db_table_creation.__dict__.iteritems():
 if isinstance(thing, sqlalchemy.ext.declarative.DeclarativeMeta) and hasattr(thing, '__tablename__'):
 models.append(thing)
</code></pre>

blocks|key|59738|text|如果您只需要这些类，那么有一个更简单的解决方案。我是在Celeo’s+answer的基础上提出的|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|59739|from+flask+import+current_app

#+This+is+to+be+generic+(ie.+no+need+to+pass+your+actual+SQLAlchemy+instance)
#+This+way+you+can+include+it+even+in+your+own+extension.
db+=+current_app.extensions['sqlalchemy'].db

[cls+for+cls+in+db.Model._decl_class_registry.values()
+if+isinstance(cls,+type)+and+issubclass(cls,+db.Model)]|code-block|syntax|javascript|59740|这不需要所有这些额外的帮助变量，只需查询类注册表，并过滤掉所有不是模型的内容。|59741|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/26518401/1305139^0|R|E|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]]|C|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|C|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]]]

If you only need the classes, there is an simpler solution. I came up with it based on <a href="https://stackoverflow.com/a/26518401/1305139">Celeo’s answer</a>:

<pre><code>from flask import current_app

# This is to be generic (ie. no need to pass your actual SQLAlchemy instance)
# This way you can include it even in your own extension.
db = current_app.extensions['sqlalchemy'].db

[cls for cls in db.Model._decl_class_registry.values()
 if isinstance(cls, type) and issubclass(cls, db.Model)]
</code></pre>

This doesn’t need all those extra helper variables, just queries the class registry, and filters out everything that is not a model.

blocks|key|59760|text|以下是我的Celeo’s+answer变体，其中包含类型和简洁的中间步骤：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|59761|from+???+import+db++#+Import+from+wherever+you+have+this,+or+use+GergelyPolonkai's+method+to+get+a+db+object.
from+typing+import+List,+Dict,+Union
from+flask_sqlalchemy+import+DefaultMeta
from+sqlalchemy.ext.declarative.clsregistry+import+_ModuleMarker

registered_classes:+List[Union[DefaultMeta,+_ModuleMarker]]+=+\
++++[x+for+x+in+db.Model._decl_class_registry.values()]
registered_models:+List[DefaultMeta]+=+\
++++[x+for+x+in+registered_classes+if+isinstance(x,+DefaultMeta)]
tables:+List[DefaultMeta]+=+\
++++[x+for+x+in+registered_models+if+hasattr(x,+'__tablename__')]|code-block|syntax|javascript|59762|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/26514823/get-all-models-from-flask-sqlalchemy-db/26518401#26518401^0|5|E|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

Here is my variation of <a href="https://stackoverflow.com/questions/26514823/get-all-models-from-flask-sqlalchemy-db/26518401#26518401">Celeo’s answer</a> with typing and succinct intermediary steps:

<pre><code>from ??? import db # Import from wherever you have this, or use GergelyPolonkai's method to get a db object.
from typing import List, Dict, Union
from flask_sqlalchemy import DefaultMeta
from sqlalchemy.ext.declarative.clsregistry import _ModuleMarker

registered_classes: List[Union[DefaultMeta, _ModuleMarker]] = \
 [x for x in db.Model._decl_class_registry.values()]
registered_models: List[DefaultMeta] = \
 [x for x in registered_classes if isinstance(x, DefaultMeta)]
tables: List[DefaultMeta] = \
 [x for x in registered_models if hasattr(x, '__tablename__')]
</code></pre>

blocks|key|59786|text|在SQLAlchemy+1.4中，_decl_class_registry.values()方法已删除，您可以改用db.Model.registry.mappers：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|59787|models+=+{
++++mapper.class_.__name__:+mapper.class_
++++for+mapper+in+db.Model.registry.mappers
}|code-block|syntax|javascript|59788|有关详细信息，请参阅this+issue。|59789|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/sqlalchemy/sqlalchemy/issues/6080^0|H|T|1L|P|0|0|A|A|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|Z|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|10|8|@]|D|@$9|11|A|12|1|13]]|E|$]]|$1|M|3|-4|5|6|7|14|8|@]|D|@]|E|$]]]|N|$O|$5|P|Q|R|E|$S|T]]]]

In SQLAlchemy 1.4, the <code>_decl_class_registry.values()</code> method has removed, you can use <code>db.Model.registry.mappers</code> instead:
<pre><code>models = {
 mapper.class_.__name__: mapper.class_
 for mapper in db.Model.registry.mappers
}
</code></pre>
See the details in <a href="https://github.com/sqlalchemy/sqlalchemy/issues/6080" rel="noreferrer">this issue</a>.

After a database is constructed in SQLAlchemy, I want to get all of the models, which is to say, the classes which represent them

<pre><code>&gt;&gt;&gt; db
&lt;SQLAlchemy engine='postgresql:///example'&gt;
&gt;&gt;&gt; ???
[&lt;db.Model 'User'&gt;, &lt;db.Model 'Comment'&gt;, &lt;db.Model 'Article'&gt;]
</code></pre>

Can this be achieved? How?

I can get the tables decently, just not the models. Eg:

<pre><code>&gt;&gt;&gt; for t in db.metadata.tables.items():
 print(t)
</code></pre>

this gives the tables just not the models themselves

Get all models from flask-sqlalchemy db

数据库

在SQLAlchemy中构建数据库后，我希望获得所有模型，也就是表示它们的类>>> db<SQLAlchemy engine='postgresql:///example'>>>> ???[<db.Model 'User'>, <db.Model 'Comment'>, <db.Model 'Article'>]这是否...

问从flask-sqlalchemy db获取所有模型
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