这句话的意思是,两张表之间的外键找不到,首先看看外键设置正确了没,如果外键没问题,看看是不是_tablename_设置了没,就是再model中,定义类的时候,表格名称要_tablename_设置一下,不设置,有时候也会报这个错。
o2.name AS PK_table, c2.name AS PK_column, pk.name AS PK_name, fk.delete_referential_action_desc AS Delete_Action, fk.update_referential_action_desc AS Update_Action FROM sys.objects o1 INNER JOIN sys.foreign_keys fk ON o1.object_id = fk.parent_object_id INNER JOIN sys.foreign_...
Today, we will learn how to find a Primary Key, Unique Key, or a Foreign Keys in a table using SQL and how to delete a primary key, unique key, or a foreign key from a table using SQL.
Flask SQLAlchemy NoForeignKeysError: 使用Flask的sqlalchemy创建表的多对多的关系的时候,一直报如下错误: sqlalchemy.exc.NoForeignKeysError: Can't find any foreign key relationships between 'publisher' and 'tb_book_publisher'. the official docs: http://docs.jinkan.org/docs/flask-sqlalchemy/models.h...
foreign key(parent_id) references parent(id) ON DELETE CASCADE ON UPDATE CASCADE ) engine=innodb; -- 被引用的表为父表,引用的表称为子表; -- 外键定义时,可以设置行为 ON DELETE 和 ON UPDATE,行为发生时的操作可选择: -- CASCADE 子表做同样的行为 ...
On SQL Server 2014 sample databaseAdventureWorks2014, when I execute SELECT command over system view sys.foreign_keys I got a huge list of foreign key constraints created on that database's tables. The foreign key name, object id, parent object id and the reference object id are some other...
@@ServerName returns wrong value in SQL SERVER 2008 ##TempTable and INSERT-SELECT FROM an existing Table with an IDENTITY column %rowtype equivalent in SQL server ++ operator in TSQL - bug or feature? 2 tables referencing each other using foreign key.is it possible 2 transactions in one sto...
ERROR 3780 (HY000): Referencing column 'UserId' and referenced column 'useridentifier' in foreign key constraint 'FK_UserRoles_oauthtokens_UserId' are incompatible. UserRoles.UserId is using the table's default character set of utf8mb4, but you're trying to make it re...
How to find the entire table list in the order of Foreign key reference in a database ie. Parent table first, then Child table RegardsBinu You can query sys.foreign_keys to get that information: SELECT [name] ConstraintName, OBJECT_NAME(parent_object_id) ReferencingTable, OBJECT_NAME (re...
I am struggling to understand the process and method of accessing the SQL table with no reference to SQL parameter or Table but string This is what I tried: Tired to create ERD diagrams and try to extract Primary and Foreign keys to associate, but I cannot in this case I would...