【sqlalchemy.exc.NoForeignKeysError：Can't find any foreign key relationships between】的更多相关文章

sqlalchemy.exc.NoForeignKeysError：Can't find any foreign key relationships between

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.…

MySQL（10）：实体、实体表和外键（foreign key）

1.实体        数据库管理系统中的各种用于数据管理方便而设定的各种数据管理对象,如:数据库表.视图.存储过程等都是数据库实体.广义上讲,这些对象中所存储的数据也是数据库实体.因为它们也是确切存在着的实体. 2.实体关系(表设计) (1)1对1的关系: 两个实体表内,存在相同的主键字段: 如果记录的主键值等于另一个关系表内记录的主键值,则两条记录的对应为1对1 对应关系 下图示例: 这里本来这里的学生主信息表 和 学生详细信息表应该水平方向上连接起来,但是这里垂直分割了,这里在优化上称之为…

flask建表遇到的错误：　flask,sqlalchemy.exc.OperationalError: (MySQLdb._exceptions.OperationalError) (1071, 'Specified key was too long; max key length is 767 bytes')

error:flask,sqlalchemy.exc.OperationalError: (MySQLdb._exceptions.OperationalError) (1071, 'Specified key was too long; max key length is 767 bytes') 分析:数据库类型字符不对(默认latin) 解决:ALTER DATABASE `databasename` CHARACTER SET utf8;…

sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) Cannot add a NOT NULL column with default value NULL [SQL: u'ALTER TABLE address_scopes ADD COLUMN ip_version INTEGER NOT NULL']

root@hett-virtual-machine:~# su -s /bin/sh -c "neutron-db-manage --config-file /etc/neutron/neutron.conf \  --config-file /etc/neutron/plugins/ml2/ml2_conf.ini upgrade head" neutronNo handlers could be found for logger "oslo_config.cfg"…

sqlalchemy.exc.CompileError: (in table 'user', column 'username'): VARCHAR requires a length on dialect mysql

映射数据库时报错:sqlalchemy.exc.CompileError: (in table 'user', column 'username'): VARCHAR requires a length on dialect mysql 错误代码: username = db.Column(db.String) String需要指定长度,如: username = db.Column(db.String(50))…

Airflow安装错误:sqlalchemy.exc.OperationalError: (_mysql_exceptions.OperationalError)

1 完整的异常信息: raise errorclass, errorvalue sqlalchemy.exc.OperationalError: (_mysql_exceptions.OperationalError) (1292, "Incorrect datetime value: '2019-10-18 13:41:07.937196+00:00' for column 'last_scheduler_run' at row 1") [SQL: u'UPDATE dag SET…

sqlalchemy.exc.InternalError: (pymysql.err.InternalError) (1091, "Can't DROP 'users_ibfk_1'; check that column/key exists") [SQL: ALTER TABLE users DROP FOREIGN KEY users_ibfk_1]

flask 迁移数据库报错 报错: sqlalchemy.exc.InternalError: (pymysql.err.InternalError) (1091, "Can't DROP 'users_ibfk_1'; check that column/key exists")[SQL: ALTER TABLE users DROP FOREIGN KEY users_ibfk_1] 解决办法: 将每个数据库表类型InnoDB转为 MyISAM 如果报错ERROR 1217 (23…

sqlalchemy.exc.InternalError: (pymysql.err.InternalError) (1366, "Incorrect string value: '\\xE6\\xB1\\x89\\xE8\\xAF\\xAD...' for column 'className' at row 1") [SQL: INSERT INTO classmessage (`classId

sqlalchemy.exc.InternalError: (pymysql.err.InternalError) (1366, "Incorrect string value: '\\xE6\\xB1\\x89\\xE8\\xAF\\xAD...' for column 'className' at row 1")[SQL: INSERT INTO classmessage (`classId`, `className`, xq, `useOrNot`, `increaseTime`…

sqlalchemy.exc.ProgrammingError: (pymysql.err.ProgrammingError)

在我学习flask建立网站时间碰到了一个棘手的问题,就是在我进行操作日志的更新时间,发现表格建立有点错误,导致表缺失,从而报了下面的错误 sqlalchemy.exc.ProgrammingError: (pymysql.err.ProgrammingError) (1146, "Table 'movie.oplog' doesn't exist") [SQL: 'SELECT oplog.id AS oplog_id, oplog.admin_id AS oplog_admin_id…

Unexpected API Error. Please report this at http://bugs.launchpad.net/nova/ and attach the Nova API log if possible. <class 'sqlalchemy.exc.OperationalError'> (HTTP 500) (Request-ID: req-6ac88345-ce5a

Unexpected API Error. Please report this at http://bugs.launchpad.net/nova/ and attach the Nova API log if possible. <class 'sqlalchemy.exc.OperationalError'> (HTTP 500) (Request-ID: req-6ac88345-ce5a-4649-8999-fa364ef4d130)…