11. last_update timestamp not null default current_timestamp on update curren_timestamp, 12. Primary key(city_id), 13. key idx_fk_country_id (country_id), 14. constraint fk_city_country Foreign Key(country_id) References country(country_id) on DELETE restrict ON update cascade 15. )eng...
旅行图 journey title Creating a View with Primary Key section Creating a View MySQL->Query: CREATE VIEW view_name AS MySQL->Query: SELECT column1, column2, ... MySQL->Query: FROM table_name MySQL->Query: WHERE condition section Setting Primary Key MySQL-->Query: CREATE VIEW view_name AS...
主键(Primary Key)是数据库表中的一列或一组列,其值用于唯一标识表中的每个记录。在创建表时,可以使用PRIMARY KEY约束来定义主键。 因为主键是用来唯一定位记录的,修改了主键,会造成一系列的影响。由于主键的作用十分重要,如何选取主键会对业务开发产生重要影响。如果我们用身份证号作为主键,似乎能唯一定位记录。然而...
so please consult your DBA beforechanging this setting. 2问题分析 从提示上可以看到具体的原因,当设置了 sql_require_primary_key 参数,不能创建或改变一张没有主键的表。解决方案是增加主键或者删除此参数避免错误,同时提醒了,如果表无主键,可能会导致基于行的复制产生性能问题。 sql_require_primary_key 参数控...
Add a primary key to the table or unset this variable to avoid this message. Note that tables without a primary key can cause performance problems in row-based replication, so please consult your DBA before changing this setting. > set sql_generate_invisible_primary_key=1; > create table ...
so please consult your DBA before changing this setting. 问题分析 从提示上可以看到具体的原因,当设置了sql_require_primary_key参数,不能创建或改变一张没有主键的表。解决方案是增加主键或者删除此参数避免错误,同时提醒了,如果表无主键,可能会导致基于行的复制产生性能问题。
Unable tocreateorchangeatablewithouta primarykey,whenthesystemvariable'sql_require_primary_key'isset.Adda primarykeytothetableorunset thisvariabletoavoid this message. Note thattableswithouta primarykeycan causeperformanceproblemsinrow-basedreplication, so please ...
so please consult your DBA before changing this setting. 问题分析 从提示上可以看到具体的原因,当设置了sql_require_primary_key参数,不能创建或改变一张没有主键的表。解决方案是增加主键或者删除此参数避免错误,同时提醒了,如果表无主键,可能会导致基于行的复制产生性能问题。
Hello guys i am with a serious problem. I have already worked with MySQL Workbench but in this version i am having big problem. When I add the setting for Auto Increment in a primary key in the table Owner and do the Forward Engineer, everything is OK. ...
without a primary key,when the system variable'sql_require_primary_key'is set.Add a primary key to the table or unsetthisvariable to avoidthismessage.Note that tables without a primary key can cause performance problemsinrow-based replication,so please consult yourDBAbefore changingthissetting. ...