foreign-keys

问题 ALTER TABLE LAB_ADMIN_USER.TEST_TEMPLATE_ABBR ADD ( CONSTRAINT TEST_TEMPLATE_ABBR_R01 FOREIGN KEY (test_template_id) REFERENCES LAB_ADMIN.TEST_TEMPLATE (test_template_id) ON DELETE CASCADE) What is the most likely cause of 'ORA=01031: insufficient privileges' when executing the command above? In other words, what permission does LAB_ADMIN_USER most likely not have? I already created the table successfully and attempted to add the FK constraint as LAB_ADMIN_USER. 回答1: The table with the

问题 We have large MS SQL database with many tables and foreign keys. We need to index all foreign keys in our tables due to performances and we are trying to avoid do it manually. Is there any way to MS SQL do it automatically or with some tools? MS SQL server used is MS SQL Server 2008 R2. Thanks a lot. 回答1: I'd steer you away from trying to do this automatically and encourage you to examine your system (Google missing index DMVs (SQL 2005 or later) for a good start) and create appropriate

问题 We have a system that allows Administrators to build out new content types within the system, including foreign key linkages to other tables. The Admin can then rebuild the database, at which point it creates the tables and all the necessary relationships, then rebuilds the EDMX and recompiles everything. Works like a champ (I didn't write it or I might know the answer to this). One drawback that we have is when a user goes to delete a record that may be linked to by an item in another table.

问题 I'm using Django's Extended User Profile and instead of having many image fields I want to make a new Images class in my models that I can upload many images which automatically get assigned to the right user. Then the user can view and edit all their images. I'm basically stuck on the last part (view and edit). My app is called ve models.py class Profile(models.Model): user = models.OneToOneField(User, on_delete=models.CASCADE) bio = models.TextField(max_length=500, blank=True) ... etc class

问题 This is not a duplicate of this post although the title is very similar. I am using EF4 with MSSQL Express 2008 R2 on VS2010. A simplified version of my schema is as follows: Table [Team]: Id (PK) Member1 Member2 Table [Person]: Id (PK) FirstName [Team].Member1 and [Team].Member2 are foreign keys pointing to [Person].Id. When generating the .edmx via VS2010, the navigation properties under [Team] become "Person" and "Person1" despite giving distinct names to the FKs inside SQLServer. Is it

问题 I am using MySQL. My question is how to automatically insert the newly added row into a foreign-key table. An example will clarify my question: I have two tables Employee and Salary: CREATE TABLE Employee( emp_id int NOT NULL AUTO_INCREMENT, name char(30), PRIMARY KEY (emp_id) ) ENGINE=innoDB; CREATE TABLE salary { sal_id int NOT NULL AUTO_INCREMENT salary_figure int, emp_id int, PRIMARY KEY (sal_id), FOREIGN KEY REFERENCES Employee(emp_id) } Here is the join table : employee_salary_join

问题 I am implementing an android application with Room database and have a small question about relationships in this DB. I have two tables: @Entity(tableName = "foods", primaryKeys = {"id", "language_id"}, indices = {@Index(value = {"id", "language_id"}, unique = true)}, inheritSuperIndices = true) public class Food { @NonNull @ColumnInfo(name = "id") private String mId; @NonNull @ColumnInfo(name = "language_id") private String mLanguageId; } @Entity(tableName = "ingredients", primaryKeys = {"id

问题 I need to add a NOT NULL column to an existing (populated) table that will be a foreign key to another table. This brings about two problems: When you add the column, its value cannot be null - using a default is not an option (unless it is removed later on) because the database logic is used in the server side validation when a user enters a new record i.e. when the application tries to add a record with this field having a null value, the database throws an error that the application

问题 I'm using phpmyadmin ( php & mysql ) and I'm having a lot of trouble linking the tables using foreign keys. I'm getting negative values for the field countyId (which is the foreign key). However it is linking to my other table fine and it's cascading fine. When I go to add data there will be a drop box for the CountyId and the values look something like this, -1 1- Here is my alter statement: ALTER TABLE Baronies ADD FOREIGN KEY (CountyId) REFERENCES Counties (CountyId) ON DELETE CASCADE 回答1:

问题 I'm using phpmyadmin ( php & mysql ) and I'm having a lot of trouble linking the tables using foreign keys. I'm getting negative values for the field countyId (which is the foreign key). However it is linking to my other table fine and it's cascading fine. When I go to add data there will be a drop box for the CountyId and the values look something like this, -1 1- Here is my alter statement: ALTER TABLE Baronies ADD FOREIGN KEY (CountyId) REFERENCES Counties (CountyId) ON DELETE CASCADE 回答1: