如果删除B表中的记录,则会级联删除A表中对应记录 createtabletest(id serialprimarykey, namevarchar(10)); createtabletest01(id serialprimarykey, tidint,constraintfk_test01_tidforeignkey(tid)referencestest(id)ondeletecascade); imos=#insertintotest(name)values('a'),('b'),('c');INSERT03imos=#ins...
postgresql外键on delete cascade 级联删除 A表中字段依赖于B表中对应字段, 如果删除B表中的记录,则会级联删除A表中对应记录 create table test(id serial primary key, name varchar(10)); 1. create table test01(id serial primary key, tid int, constraint fk_test01_tid foreign key(tid) references te...
当尝试删除一个被ON DELETE RESTRICT约束引用的数据行时,PostgreSQL会抛出一个错误,阻止删除操作。这个错误表明删除操作违反了外键约束,因为还有其他数据行依赖于这个数据行。 提供与"ON DELETE RESTRICT"相关的其他级联删除选项的简要说明: ON DELETE CASCADE:当被引用表中的数据行被删除时,引用表中所有引用该数据行...
复制 $table->foreign('post_id')->references('id')->on('posts')->cascadeOnDelete(); 确保数据库引擎支持级联删除:在使用cascadeOnDelete之前,需要确保数据库引擎支持级联删除。大多数常见的数据库引擎(如MySQL、PostgreSQL)都支持级联删除,但某些数据库引擎可能不支持。在使用之前,请确保你使用的数据库引擎支持...
PostgreSQL Alter Table Exercises: Write a SQL statement to add a foreign key constraint named fk_job_id on job_id column of job_history table referencing to the primary key job_id of jobs table.
PostgreSQL 其他常见约束语法添加 1. 添加主键altertablegoodsaddprimarykey(sid); 2. 添加外键altertableordersaddforeignkey(goods_id)referencesgoods(sid)onupdatecascadeondeletecascade;onupdatecascade: 被引用行更新时,引用行自动更新;onupdaterestrict: 被引用的行禁止更新;ondeletecascade: 被引用行删除时,引用行也...
on_delete=models.CASCADE“不生成级联外键约束？EN我正在使用Django、Python3.7和PostgreSQL 9.5。如何...
The System.DateOnly and System.TimeOnly types were introduced in .NET 6 and have been supported for several database providers (e.g. SQLite, MySQL, and PostgreSQL) since their introduction. For SQL Server, the recent release of a Microsoft.Data.SqlClient package targeting .NET 6 has allowed...
Same here but with PostgreSQL. Any ideas? ngocketit commented Oct 14, 2021 I noticed that this won't work: type Option struct { Base Content string `gorm:"not null"` QuestionID string `gorm:"not null"` Question *Question `gorm:"constraint:OnDelete:CASCADE;"` } type Question struct ...
ON DELETE CASCADEdoes not work for some partitioned tables. Affected instances will contain tables with records that need to be deleted constraints that need to be recreated (Additionally, they'll need to upgrade to a fixed PostgreSQL version - that isn't in scope for this issue!) ...