What is a trusted constraint in SQL Server? Many experts do not know, so instead of a definition I explain it with a simple check constraint example.
How to Create Primary Key Without ANY Index? – Interview Question of the Week #143
Question: How to create primary key without ANY index? SQL Server builds a clustered or nonclustered index for every primary key, so here is the answer.
SQL SERVER – How to Find UNIQUE Key Columns? – sp_special_columns
Want to know which columns uniquely identify a row in a table? The system stored procedure sp_special_columns tells you. Here is a quick demo.
How to Allow Only Alphabets in Column? – Interview Question #136
Question: How to Allow Only Alphabets in Column? Answer: This was a real world scenario and I have mixed feeling about this kind of question.
SQL SERVER – FIX: Rule “Reporting Services Catalog Database File Existence” Failed
After a disaster, a client’s SQL Server setup failed the rule Reporting Services catalog database file existence. Here is why and how I got the install through.
How Many Foreign Key Can You Have on A Single Table? – Interview Question of the Week #096
How many foreign key references can you have on a single table? I said 253 at SQLPASS, but my answer was not complete. Here is the full answer.
MySQL – Fix Error – WordPress Database Error Duplicate Entry for key PRIMARY for Query INSERT INTO wp_options
My blog was slow and scheduled posts failed. The cause was a Wordpress Database Error: duplicate entry for key PRIMARY in wp_options. Here is how I fixed it.