I agree naming constraints is a good plan but, in SQL Server 2008 R2 at least, the syntax of the last line has to be "constraint fk_questionbank_exams foreign key (question_exam_id) references exams (exam_id)"

Your problem isn't in the Primary Key on SIGNAL_RECEIVINGS, that will work just fine. Your problem is that you have id_chip with a foreign key to SIGNALS, and Signal_no with a foreign key to SIGNALS, both referencing a single column. Given that the PK on SIGNALS is a composite key, your FK on SIGNAL_RECEIVINGS needs to also be a composite to ...

Your table dbo.Sup_Item_Cat has a foreign key reference to another table. The way a FK works is it cannot have a value in that column that is not also in the primary key column of the referenced table. If you have SQL Server Management Studio, open it up and sp_help 'dbo.Sup_Item_Cat'. See which column that FK is on, and which column of which ...

Apr 18, 2011 · I want to know the use of foreign key in SQL Server as I had a debate with one of my colleagues. I have the opinion, when two tables are connected via a foreign key, when the records are deleted from the parent table then the same reference record from the child table should also get deleted. Say for example I have two tables, Table1 and Table2.

Aug 31, 2015 · Since the foreign key is pointing to another table's primary key, this is why you need to specify the foreign key's datatype. And it obviously needs to be the same datatype. EDIT: SQL implementations are lax on this case as we can see: they do allow compatible types (INT and BIG INT, Float or DECIMAL and DOUBLE) but at your own risk. Just as we ...

Oct 31, 2008 · Using MSSQL2005, can I truncate a table with a foreign key constraint if I first truncate the child table (the table with the primary key of the FK relationship)? I know that I can either Use a D...

Jan 27, 2009 · Works great! It'd be even better if you: a) prefix all Column Names with "Fk" / "Key"), b) suffix all Column Names with "Name", c) remove underscores, d) add KeyTableSchemaName, e) add default order by: KeyTableSchemaName, KeyTableName, KeyColumnName, FkTableSchemaName, FkTableName, FkName, and f) change Column …

Aug 3, 2016 · Here is the sql generated by sqlserver after I use the database diagram to draw the foreign key. Their approach is that one alter table for one foreign key

Mar 4, 2013 · I have a SQL-Server 2008 database and a schema which uses foreign key constraints to enforce referential integrity. Works as intended. Now the user creates views on the original tables to work on subsets of the data only. My problem is that filtering certain datasets in some tables but not in others will violate the foreign key constraints.

So it is always recommended to insert only those values in the Foreign key column which are present in the Primary key table column. For ex. If the Primary table column has values 1, 2, 3 and in Foreign key column the values inserted are different, then the query would not be executed as it expects the values to be between 1 & 3.