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- What is a proper naming convention for MySQL FKs?
The reason for creating a symbolic name is for referencing when you want need to drop the constraint Oracle SQL Server allow you to disable specific constraints If you don't have fk in the name, you have to confirm the constraint is a foreign key constraint
- Differences between foreign key and constraint foreign key
The first one assigns a user-defined name to the foreign key, the second one will assign a system-generated name to the foreign key User-defined foreign key names can be useful for subsequent statements like these: ALTER TABLE XTable DROP CONSTRAINT fk_idq; ALTER TABLE XTable ENABLE CONSTRAINT fk_idq; ALTER TABLE XTable DISABLE CONSTRAINT fk_idq; It's harder to alter constraints with system
- List of foreign keys and the tables they reference in Oracle DB
I'm trying to find a query which will return me a list of the foreign keys for a table and the tables and columns they reference I am half way there with SELECT a table_name, a column_n
- How can I list all foreign keys referencing a given table in SQL Server . . .
I need to remove a highly referenced table in a SQL Server database How can I get a list of all the foreign key constraints I will need to remove in order to drop the table? (SQL answers prefera
- How to find foreign key dependencies in SQL Server?
How can I find all of the foreign key dependencies on a particular column? What are the different alternatives (graphically in SSMS, queries views in SQL Server, 3rd party database tools, code in
- mysql - Add Foreign Key to existing table - Stack Overflow
I want to add a Foreign Key to a table called "katalog" ALTER TABLE katalog ADD CONSTRAINT `fk_katalog_sprache` FOREIGN KEY (`Sprache`) REFERENCES `Sprache` (`ID`) ON DELETE SET NULL ON UPDATE
- How do I create a foreign key in SQL Server? - Stack Overflow
This script is about creating tables with foreign key and I added referential integrity constraint sql-server create table exams ( exam_id int primary key, exam_name varchar(50), ); create table question_bank ( question_id int primary key, question_exam_id int not null, question_text varchar(1024) not null, question_point_value decimal, constraint question_exam_id_fk foreign key references
- Does a foreign key automatically create an index?
An FK-relationship will often need to look up a relating table and extract certain rows based on a single value or a range of values So it makes good sense to index any columns involved in an FK, but an FK per se is not an index Check out Kimberly Tripp's excellent article "When did SQL Server stop putting indexes on Foreign Key columns?"
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