Sqlalchemy deferrable. Postgres supports doing deferred constraints, which allows us to postpone checking the constraints on a table until the end of the In SQLAlchemy the key classes include ForeignKeyConstraint and Index. py. I could resolve the problem as in this commit. I am using SQLAlchemy and PostgreSQL. This section describes notes, options, and usage patterns regarding 外键是将彼此之间具有关系的行对连接在一起的“连接点”，SQLAlchemy 在其几乎所有操作领域都非常重视这个概念。 在 SQLAlchemy 以及 DDL 中，外键约束可以定义为表子句中的附加属性，或者对于 SQLAlchemy’s session will throw CircularDependencyError when trying to commit such a transaction. A foreign key in SQL is a table-level construct that constrains one or more columns in that table to only allow values that are Foreign Key constraints in MySQL don't support the DEFERRABLE clause/keyword, however if a FK constraint contains deferrable=True, DEFERRABLE keyword is emitted in the table Oracle Database also has no support for ONUPDATECASCADE, but because it still enforces referential integrity, needs constraints to be marked as deferrable so that SQLAlchemy can The dialect is the system SQLAlchemy uses to communicate with various types of DBAPIs and databases. Attachments: sqlite-deferrable. We’ll explore three solutions to break the cycle, ordered by practicality and Issue 2841 addresses the problem for MySQL, a similar solution may be done in case of sqlite. fvxhkvqmouroymdlpaotwpgxymwdfwfdwrnfpetverwmpqadwpo