Back in the 90s, I remember getting a project from a local F500 company. Our design team had been doing some work for them and they'd been happy with the results so when they had problems on a backend project which was over a year behind schedule they asked if we could help & I was pulled in. The project was a fairly straight forward product selector for industrial equipment but the team from a large consulting firm which had been working on it was struggling with performance & hadn't completed most of the features. The client was saying it was unacceptable that pages would take 5 or more minutes to load and they weren't going to drop $500K on bigger servers like the developers were swearing were necessary to run the site.
I knew something was off performance-wise since the entire product catalog was only on the order of tens of thousands of records. As soon as I looked at the source code, the mystery was explained: they had allegedly experienced 3 developers working on it but none of them knew about SQL WHERE constraints! Instead, they were doing nested for loops to repeatedly retrieve every row of every table and doing the equality checks in VBScript. Finishing the rest of the project backlog took me a couple of days and the customer was quite happy that the slowest pages were now measured in hundreds of milliseconds rather than tens of minutes.
I was proud of how quickly we were able to turn that project around but the PM & I were discussing how even our rush rate wasn't enough to get us anywhere close to the amount of money the previous contractors had charged.
I knew something was off performance-wise since the entire product catalog was only on the order of tens of thousands of records. As soon as I looked at the source code, the mystery was explained: they had allegedly experienced 3 developers working on it but none of them knew about SQL WHERE constraints! Instead, they were doing nested for loops to repeatedly retrieve every row of every table and doing the equality checks in VBScript. Finishing the rest of the project backlog took me a couple of days and the customer was quite happy that the slowest pages were now measured in hundreds of milliseconds rather than tens of minutes.
I was proud of how quickly we were able to turn that project around but the PM & I were discussing how even our rush rate wasn't enough to get us anywhere close to the amount of money the previous contractors had charged.