Facilities provided by a database management system to ensure consistency within the data.

learn more… | top users | synonyms

0
votes
1answer
63 views

SQL - referential integrity - Foreign key and Check constraint

Please let me know if below two declarations are same. create table R1 ( a INT PRIMARY KEY, b INT references K(w)); Note: K is a table with single attribute w as primary key create table R1 ( a ...
2
votes
0answers
53 views

Any drawbacks to referencing multiple tables from a single column?

I'm working on a system with the following entities: Projects Sections Activities There is one important constraint that needs to be enforced: Activities are always part of one project. ...
2
votes
0answers
46 views

SQL Server 2005 Datawarehouse DB - Integrity failure caused by NonClustered indexes

Last year I've been working with a data warehouse database (SQL Server 2005) loaded on a daily basis during the nights. Overall database performance is acceptable. However, there is a "known error" ...
2
votes
0answers
173 views

Maintaining Referential Integrity with a Filestream enabled database

We have a production database which is filestream enabled and has grown, within a year, to about 20Gb as it stores documents. On many occasions we need to bring the live data back to UAT or Dev ...
1
vote
0answers
26 views

Visualize the effects of a cascading delete or update?

In MySQL, I'm working with a database that has integrity constraints on foreign keys (nothing overly special here). Is there a method to somehow visualize the effects of a cascading delete or update? ...
1
vote
0answers
42 views

How do I disable constraint checking during schema migration?

How do I disable FOREIGN KEY checking for the time of database schema migration? Currently I found engine-based commands like: PostgreSQL: SET CONSTRAINTS ALL DEFERRED; MSSQL: EXEC ...
1
vote
0answers
43 views

Constraint across multiple tables

I'm modeling a system where with vendors, each of which sells some overlapping subset of products available in the universe. Products (T-shirt) come in various variants (Small, Medium, Large) with ...
1
vote
0answers
36 views

Enforce referential integrity for FriendRequest table that has UserA and UserB

I have a table called User that has UserName as a primary key. I want to establish a relationship with enforced referential integrity between User and FriendRequest. FriendRequest has the following: ...
0
votes
0answers
311 views

insert record to child table which doesn't map to parent table - possible?

Actually I've 2 relevant questions: insert record to child table which doesn't map to parent table - possible? ON DELETE NO ACTION - when a record in parent table is deleted, it should affect ...