![]() ![]() ![]() I think you should read Flask SqlAlchemy's One-to-Many Relationships for more details. Within the Column object, there are individual parameters sqliteonconflictnotnull, sqliteonconflictprimarykey, sqliteonconflictunique which each correspond to the three types of relevant constraint types that can be indicated from a Column object. It does not allow you to assign variable like d = Alert(88, 'trdft') Name = db.Column(db.String(ALERT_NAME_MAX_SIZE), nullable=False) In the exception, the INTEGER PRIMARY KEY becomes an alias for the rowid. The exception to this rule is when the rowid table declares an INTEGER PRIMARY KEY. User_id = db.Column(db.BigInteger, db.ForeignKey('er_id'), nullable=False) The PRIMARY KEY of a rowid table (if there is one) is usually not the true primary key for the table, in the sense that it is not the unique key used by the underlying B-tree storage engine. ![]() User_id = db.Column(db.BigInteger, primary_key=True)Īlerts = db.relationship('Alert', backref='user', lazy='dynamic')Īlert_id = db.Column(db.Integer, primary_key=True, autoincrement=True) This is perhaps the least interesting benefit. The schema also has the foreign key constraint set on the child keys. Ive successfully setup a schema of 4 tables, each having a foreign key pointing to its parent table. One must also know/inspect the data model or make assumptions based on the naming of columns and tables. Im relatively new to sqlite and databases in general. I have an issue with foreign key in Flask. Explicit direction of the join In a traditional join on foreign key columns, its not possible to derive if the join is a one-to-many or many-to-one join, by just looking at the SQL code itself. ![]()
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