Postgres and Indexes on Foreign Keys and Primary Keys
Does Postgres automatically put indexes on Foreign Keys and Primary Keys? How can I tell? Is there a command that will return all … Read more
foreign-keys
How to select rows with no matching entry in another table?
I’m doing some maintenance work on a database application and I’ve discovered that, joy of joys, even though values from one table are … Read more
When to use “ON UPDATE CASCADE”
I use ON DELETE CASCADE regularly but I never use ON UPDATE CASCADE as I am not so sure in what situation it … Read more
MySQL DROP all tables, ignoring foreign keys
Is there a nice easy way to drop all tables from a MySQL database, ignoring any foreign key constraints that may be in … Read more
Cannot truncate table because it is being referenced by a FOREIGN KEY constraint?
Using MSSQL2005, can I truncate a table with a foreign key constraint if I first truncate the child table (the table with the … Read more
What is related_name used for?
What is the related_name argument useful for on ManyToManyField and ForeignKey fields? For example, given the following code, what is the effect of … Read more
How do I see all foreign keys to a table or column?
In MySQL, how do I get a list of all foreign key constraints pointing to a particular table? a particular column? This is … Read more
How to truncate a foreign key constrained table?
Why doesn’t a TRUNCATE on mygroup work? Even though I have ON DELETE CASCADE SET I get: ERROR 1701 (42000): Cannot truncate a … Read more
How can foreign key constraints be temporarily disabled using T-SQL?
Are disabling and enabling foreign key constraints supported in SQL Server? Or is my only option to drop and then re-create the constraints? … Read more