Large Application Estimation in 2 Weeks

This is post 2 from a 7 part series entitled Technical Achievements in my Last Project. My role in this project started out by being asked to assess the existing project, provide insight into options to move it forward, with one of those options being a rewrite*. An estimation was needed for the rewrite option, so I was given 2 weeks to do it. This post explains how I was able to pull off this massive estimation undertaking in a mere 2 weeks. Ideally, the project documentation from the existing system could be used to give an excellent estimate, but this is a blog post, not a fairly tale. Or a thorough specification could have derived from an in depth analysis of the existing application, which business could have adjusted as needed, and used to conclude a reasonable estimate. But this is the real world, and this is a real business; and I was given a real (short) deadline. Now I should also mention this wasn’t a 20 KLOC project, it was a fairly complex piece of software with over 500 KLOC** and almost 1800 database objects along with satellite applications. Everybody understood how this short timeframe severely limited the accuracy of anything I would be able to provide, but I was determined do the best job possible. So my next goal was to figure out how to do a somewhat accurate estimate, provided the constraints, where I wouldn’t be setting myself up for a lynching at the end of it. I explored many different ways to get a rough idea about the entire projects scope. This is what I finally settled on: Dumped all Microsoft Access Objects First I modified an Access VBA script I found for exporting objects to text files and exported everything. Dumped all database DDL I wrote a little command line utility to loop through a SQL Server database, pull the DDL for each object using the sp_helptext stored procedure, and write it out to text files. Created an analysis database Created an analysis database primarily comprised of three tables; one for all the entities the application is comprised of, a second for linking which entity called which, and the third for linking menu items to all dependent forms. Collected the names of all objects into the database I wrote another little command line utility to read each code file dumped out in steps 1 & 2, and add the objects name and a... read more

The CRUDLAFS Technique for Software Estimation

I have always, like so many other programmers, had a problem with software estimation and costing out a software project. Most of my career was plagued by software estimates so bad that I made significantly less money on my independent projects than I did at my low paying day jobs. This was not the reason I was working through my vacations! The turning point came when I realized the CRUD acronym encompassed most of the functionality of the line of business applications I was writing and could be used as a check list to ensure I wasn’t missing functionality. Later, this checklist was refined to CRUDLAFS. Wait! What? CRUDLAFS? … did I just coin a new acronym? …. Hmmm, looks like I did!</egosmirk> While I’m sure you are already familiar with the CRUD acronym, here is CRUDLAFS: Create All functionality around validating and creating an entity Read All functionality around reading and displaying an entity Update All functionality around validating and updating an entity Delete All functionality around deleting an entity List All functionality around querying and displaying a list of entities Additional  All additional functionality related to an entity Filter All functionality around filtering a list of entities Sort All functionality around sorting a list of entities I set up an Excel spreadsheet with CRUDLAFS as column headings, all my known or probable entities down the left, and probable hours to accomplish each in the cells, like so: So in my example, the estimated time to create a list of orders is 5 hours. And when I say known or probable entities, I mean; on smaller projects, I usually have a pretty good idea what all the entities will be, but on big projects, I charge hourly until requirements, data model, GUI design / functional specifications, and initial risk assessment is complete. Most larger projects just have too much back and forth communication and the customer usually doesn’t even have more than a vague idea of what they want. This was a very important distinction which has kept me out of bankruptcy. I get the feeling this may not work well with agile approaches, but for Big Design Up Front projects, it has been a major leap for me. Copyright © John MacIntyre 2010, All rights... read more