Here's the LAG version:

CREATE TABLE #yourtable (
    thedate datetime NOT NULL,
    agent int NOT NULL,
    AgentName varchar(11) NOT NULL,
    category varchar(7) NOT NULL
);
INSERT INTO #yourtable...

If you can get past the crisis, you may want to look at a good solid jump in the overall RAM on this box.   You stated you have an 800...

Here's the how on implementing the CASE statement:

DECLARE @col1 AS int = 255;

DECLARE @col2 AS char(1) = 'X';
DECLARE @IsEmp AS varchar(1) = 'N';
DECLARE...

Well, one thing you might want to know is just how much RAM there is on this server.   I was looking at a few posts during the last week on...

I'm wondering how you would represent that a teacher decides that an absent student without a viable excuse for that absence gets an assigned score of 0 for that exam,...

Ed, I agree with you 100%.   Mr. Celko posts in a manner that makes people feel disrespected, and frankly, I'm sick of seeing it.   It's a shame this forum did...

When you say compare column by column, does that mean ALL columns?   Are the number of columns; and the names thereof; in both result sets, the same?
If so, you...

Nope.  Never seen it.   However, a couple of things to check:

1.) properties of the tablix cell - in particular, visibility.  Be sure it's set to be visible.
2.)...