microsoft sql

SQL201

Correlated Subqueries in a HAVING Clause

Using sub queries in the HAVING clause is little different than using a sub query in any other part of the clause. The one thing that may through you is the

SQL102

UPDATE Triggers

Last time we discussed triggers, we covered insert triggers. This time we're doing UPDATE triggers. All the same rules apply to UPDATE triggers that apply to

t-sql

Correlated Subqueries with Comparison Operators

If you haven't used a sub query yet, I'm surprised. They can be incredibly useful. They can also be a crutch...but like I say time and again, each tool has it's

SQL201

Correlated Sub Queries with Aliases

I know I've covered sub queries before, but I wanted to make sure I made a specific point. When you create a correlated sub query, you can reference columns

SQL201

COUNT(*) vs COUNT(columnName)

Let's look at the following code using your copy of AdventureWorks. USE AdventureWorks GO SELECT COUNT(*) AS countStar , COUNT(ALL EmployeeID) AS

SQL201

Correlated Subqueries

The fundamental idea behind sub queries is you execute the sub query once, then take the value(s) from that sub query and substitute them in place of the sub

SQL201

Error Number

Every error generated in Microsoft SQL has a specific number, this number should uniquely identify the error that has occurred. This can be useful in building

t-sql

Insert Triggers

An insert trigger is a Data Manipulation Language (DML) trigger that acts when a new record is added to the table. CREATE TRIGGER t_tableName_insert ON

SQL102

SQL 102 – REVOKE

Like I mentioned previously REVOKE is like an undo function for GRANT and DENY. If you have a developer and you work with him for a while, you may find that

dba

SQL 102 – DENY

Alright, at this point you should know how to GRANT permission to a database object, but do you know how to DENY permission to an object? DENY uses a syntax

SQL301

Intro to XML, Part The Second

Last time I gave you a short introduction into XML. I covered the very beginning of what it is, what you use it for, and I even showed you an example file. This

SQL301

XML, in as Few Posts as Possible

Ok, I know I have a few groups of posts started, so you won't mind me starting another one, right? Right, so this collection of posts will be all about XML. If