Author: Created: 9/30/2008 8:59 PM Commentary from the WestClinTech function designers.

## Calculating percentiles in SQL Server

By Charles Flock on 7/15/2011 5:21 PM

Using the XLeratorDB/statistics 2008 PERCENTILE and PERCENTRANK functions in SQL Server 2008.

## Calculating Internal Rates of Return in SQL Server for multiple periods and multiple holdings

By Charles Flock on 5/19/2011 6:37 PM
In the article we will look at how we can use the XLeratorDB XIRR function to calculate the internal rate of return for individual securities in a portfolio as well as for all the securities in a portfolio, across multiple time horizons.

## Calculating Exponential Trendline Values in SQL Server

By Charles Flock on 5/14/2011 1:22 PM

In this posting we demonstrate how to replicate the EXCEL Exponential Trendline in SQL Server using XLeratorDB.

## Calculating Trendline Values in SQL Server Using XLeratorDB

By Charles Flock on 4/26/2011 5:33 PM

In this posting we demonstrate how to replicate the EXCEL Polynomial Trendline in SQL Server.

## New SQL Server Interpolation Functions in XLeratorDB

By Charles Flock on 4/20/2011 5:02 PM

A look at the new interpolation functions in XLeratorDB/math2008 written specifically for SQL Server 2008.

## Calculating Pascal’s Triangle in SQL Server

By Charles Flock on 3/15/2011 7:07 PM

We demonstrate the kind of things that you can do in SQL Server using the XLeratorDB function library. Would you ever really need to build Pascal’s triangle in T-SQL? Probably not. But you really don’t need to build it in any programming language, yet when I search on ‘programming Pascal’s Triangle’ in Google I get about 139,000 results. Now there’s one more.

## What’s new in XLeratorDB/statistics 2008 v1.08

By Charles Flock on 3/7/2011 10:10 PM

A look at the 32 new aggregate functions in XLeratorDB/statistics2008 v1.08.

## How about a date (function)?

By Charles Flock on 2/14/2011 9:33 PM
We added 3 new date functions to XLeratorDB/financial that should make date calculations and date manipulations much easier and more EXCEL-like, and show you how to use them to calculate things like date of Easter.

## Growing Annuities

By Charles Flock on 2/13/2011 3:43 PM

We added 4 new functions to deal with growing annuities, where the initial payment increases by a fixed percentage each period, making it far simpler to answer questions like how much do I need to save for retirement?

## Enhanced Present and Future Value Calculations

By Charles Flock on 2/13/2011 3:42 PM
In addition to the new multi-input aggregates available in XLeratorDB/financial 2008, we have added some new scalar functions that provide even greater flexibility for time-value-of-money calculations.

## Powerful new aggregate functions in XLeratorDB/finance 2008

By Charles Flock on 2/13/2011 3:41 PM
With the release of XLeratorDB/finance2008, the XLeratorDB/financial package makes innovative use of the multi-aggregate input capabilities of SQL Server 2008, improving performance in some calculations over 50-fold. In addition, there are some new functions that EXCEL wishes it had.

## Backing up and Restoring XLeratorDB

By Charles Flock on 2/5/2011 10:12 PM

If, like me, you make a backup of your production database and restore that backup on a different machine for reporting, testing, development or any other reason, you need to make sure that your XLeratorDB licenses are properly synchronized.

## Multi-input Aggregates in SQL Server 2005

By Charles Flock on 1/8/2011 1:37 PM
Despite what Books-on-line and other Microsoft documentation tells you, it is possible to implement multi-input aggregates in SQL Server 2005, albeit with some restrictions.

## The Art of the Function

By Charles Flock on 12/13/2010 11:01 PM
A look at the PV calculation and why it’s easier to use a function even when we can replicate the calculation in T-SQL.

## Time Value of Money Problems in EXCEL

By Charles Flock on 11/18/2010 6:09 PM
How a simple table-valued function led to a deep dive into the time value of money functions in EXCEL where we discover that the EXCEL IPMT and PPMT functions are broken for payments made at the beginning of the period—even in EXCEL 2010.

## Finance 1.06 is available

By Charles Flock on 11/14/2010 7:33 PM
Finance version 1.06, with 19 new functions (not found in EXCEL) is now available.

## Time-Weighted Rate of Return

By Charles Flock on 10/14/2010 5:35 PM
We frequently get inquiries about whether or not XLeratorDB can perform a time weighted return calculation. The Modified Dietz function (MDIETZ and MDIETZ_q) is just such a calculation. However, we have come up with another technique using the RATE and FVSCHEDULE functions that performs a daily time-weighted return calculation that you may find useful.

## Introducing XLeratorDB/statistics for SQL Server 2008

By Charles Flock on 10/8/2010 8:20 AM
We have changed 14 scalar functions to take advantage of the multi-input aggregate capabilities of SQL Server 2008 and improved performance more than twenty-five-fold.

## One pass or two?

By Charles Flock on 9/29/2010 5:18 PM
A look at the numerical accuracy of SQL Server’s aggregate functions, the limits of floating-point math, and other interesting stuff we discovered while implementing multi-input aggregate functions in SQL Server 2008.

## New Statistics Package

By Charles Flock on 9/6/2010 3:24 PM

Information about the release of XLeratorDB/statistics version 1.06

## The case against Treasury Bonds

By Charles Flock on 9/3/2010 8:13 AM

Are Treasury Bonds really a risk free investment?

## The Epistemological Question

By Charles Flock on 7/7/2010 5:12 PM
How do you know if a function is accurate?

## XLeratorDB/developer now available

By Charles Flock on 6/27/2010 2:37 PM

We are pleased to announce the availability of XLeratorDB/developer at the startling price of \$149.99

## The Monty Hall Problem

By Charles Flock on 6/8/2010 5:04 PM
Using the SeriesInt function to create a Monte Carlo simulation analyzing a classic probability problem.

## It aint over ‘til it’s over

By Charles Flock on 5/18/2010 8:19 PM
When is it time to admit that your favorite baseball team is not going to play in the post-season?

## Loan Calculations in EXCEL

By Charles Flock on 5/10/2010 5:59 PM
EXCEL 2010 [beta] documentation uses the phrase ‘the following functions have improved accuracy.’  But what does that actually mean in relation to the IPMT, PPMT, CUMPRINC, and CUMIPMT functions?

## New Statistics Release

By Charles Flock on 5/2/2010 4:12 PM
XLeratorDB/statistics version 1.05 contains eight new chi-squared functions that give you the flexibility to enter the expected results.

## Undocumented improvements to XIRR in EXCEL 2010

By Charles Flock on 4/26/2010 5:22 PM
XIRR in EXCEL 2010 is greatly improved over 2007, but you won’t find it mentioned in the literature.

## XLeratorDB/financial 1.05 is now available

By Charles Flock on 4/19/2010 5:49 PM
We’ve added monthly coupons to the bond functions, a new bond interest function, and some tweaks to XIRR

## EXCEL YIELD function gives incorrect results

By Charles Flock on 4/7/2010 6:23 PM

Wherein we delve deep into EXCEL’s YIELD function and discover the inconsistencies between the YIELD function and the PRICE function in EXCEL.

## 401(k) calculator in SQL Server

By Charles Flock on 3/5/2010 9:09 PM

Using the FV function to calculate the value of your 401(k) when you retire.

## More problems with the XIRR function in EXCEL

By Charles Flock on 2/3/2010 6:27 PM
As a follow up to our previous blogs documenting problems with the XIRR function in EXCEL and what an EXCEL XIRR of 2.98023E-09 really means.

## Creating a loan amortization schedule in SQL Server

By Charles Flock on 2/2/2010 6:24 PM
Using the PV, IPMT, PPMT, and PMT functions in XLeratorDB/financial to create a loan amortization schedule in a SELECT statement in SQL Server.

## SQL Server Matrix Functions

By Charles Flock on 1/21/2010 8:50 PM
With the latest release of XLeratorDB/math, we add functions for calculation of the matrix product, the matrix determinant, and the matrix inverse.

## Happy Holidays

By Charles Flock on 12/14/2009 8:12 PM

A look at the XLeratorDB JOINSTR function.

## Calculating Life Expectancy in SQL Server

By Charles Flock on 11/27/2009 4:36 PM

How a simple function like PRODUCT can profoundly change the capabilities of T-SQL

## New Interpolation functions in XLeratorDB

By Charles Flock on 10/19/2009 5:34 PM

A brief description of the new functionality in Math release 1.02

## An Historic Trough

By Charles Flock on 10/15/2009 6:19 PM

A quick look at some business intelligence that you won’t get on most dashboards.

## Monte Carlo Simulation in SQL Server

By Charles Flock on 8/24/2009 3:50 PM
A brief introduction to some techniques that will allow you to run Monte Carlo simulations in your SQL Server database using XLeratorDB functions.

## Normalizing Data with the PARSE function

By Charles Flock on 7/31/2009 4:07 PM
In this article we discuss the ease with which a string of delimited data can be converted to normalized data by using the XLeratorDB PARSE function.

## ODDFPRICE calculation differences between EXCEL and XLeratorDB

By Charles Flock on 7/14/2009 6:43 PM
If you use the EXCEL ODDFPRICE to calculate the price of a bond with an odd first coupon period, you should read this article to find out when those calculations are incorrect. Specifically, by using the EXCEL PRICE function you will discover the following three problems with the ODDFPRICE function...

## COUPDAYS difference between XLeratorDB and EXCEL

By Charles Flock on 6/30/2009 6:08 PM

A brief explanation on why the XLeratorDB implementation of this function is different than the EXCEL implementation.

## A Black-Scholes Option Calculator as a Table-Valued-Function

By Charles Flock on 5/20/2009 8:51 PM
In this blog I will demonstrate how to build a simple Black-Scholes options calculator by creating a table-valued function and using the XLeratorDB/statistics functions module.

## XLeratorDB/strings is now available

By Charles Flock on 5/8/2009 11:55 AM

Some notes on the release of the strings package and how it works in relation to EXCEL and to some existing built-in SQL functions.

## It's Opening Day!

By Charles Flock on 4/8/2009 7:07 PM
Using the XLeratorDB/statistics module to calculate some baseball statistics

## XLeratorDB/engineering is now available

By Charles Flock on 4/3/2009 5:28 PM
Some notes on the release of the engineering package and how it works in relation to EXCEL.

## Why XLeratorDB is the right tool for the financial crisis

By Charles Flock on 3/12/2009 7:19 PM
A brief discussion about the advantages of XLeratorDB over the combination of EXCEL and SQL Server, or, as we like to put it, a proof of the equation:
XLeratorDB > SQL Server + Excel

## XLeratorDB/statistics is now available

By Charles Flock on 3/2/2009 2:16 PM

Some notes on the release of the statistics package and how it works in relation to EXCEL and in relation to existing SQL Server functions with the same or similar names.

## What is Normal?

By Charles Flock on 2/24/2009 7:41 PM

One of the big problems that you may have in moving from the spreadsheet paradigm to the database paradigm is in ‘normalizing’ your data. In this article, I will attempt to explain what that means.

## Writing your own functions using XLeratorDB

By Charles Flock on 1/11/2009 4:39 PM

Build your own mortgage calculator using XLeratorDB/financial.

## Search Blogs

 KeywordsPhrase

## Blog Archives

Archive
 < July 2011 >
SunMonTueWedThuFriSat
262728293012
3456789
10111213141516
17181920212223
24252627282930
31123456
Monthly
Go