When it comes to software, the concept of time can cause problems. There’s actually some really interesting scenarios, but even in simple applications, some developers really struggle with simple concepts.

In terms of standard problems, you can have problems where the client and server times can be out. This can just be because they are set incorrectly, or maybe are using a different timezone. As a developer, if you are looking at times in log files across the client and server, it can cause confusion if the timestamps are out. A common thing I have seen is that some servers don’t use Daylight Savings Time we have in the UK, but the client times often do. So the server can be an hour out.

Daylight savings time is interesting as time shifts forward or backwards one hour. So time isn’t linear.

I recall reading a blog about time by Jon Skeet who then discussed how if you are using historical dates, the time can also suddenly change. Like if a country switches to a different calendar system entirely, so moving a day could suddenly jump in years to align with the new system.
Computerphile have a discussion on this The Problem with Time & Timezones – Computerphile

Leap Years

We once had a leap year bug because someone created a new date using the current day and month, and added a year. So when it was 29th Feb, it tried to create a date of 29th Feb for next year which wasn’t a valid date. So the feature crashed. Everyone was panicking trying to rush out a fix, but then we realised we could only get the fix out to our customers tomorrow, and the bug wouldn’t happen. Not for another 4 years anyway. It was hilarious

-1

One weird mistake I saw recently, is that a developer defined a variable and set it to 5. The code they wrote was supposed to make sure that we never make an API call more than once every 5 minutes. However, they then minused 1, so were checking every 4 minutes instead.

var minimumNumberOfSecondsRequiredBetweenEachAPICall = (NumberOfMinutesRequiredBetweenEachAPICall - 1) * 60;

Ages

You would think everyone would understand the concept of ages since everyone has an age and it increases by 1 every time you have a birthday. However, many developers seem to struggle with the concept. The last implementation I saw had the following:

int age = DateTime.Now.Year - dateOfBirth.Year;

So it can be one year out because it basically assumes your birthday is 1st January.

It reminds me of an exchange on Twitter that I saw years ago. It was in the context of football.

PA: Why are Arsenal paying £25m for a 29 year old striker?
G: he’s 28 btw
PA: He’s a lot nearer to 29 than 28, that’s a fact
G: He’s 28, that’s a fact
PA: Why am I not surprised that fractions are beyond you. The day after his birthday, he is no longer 28.
G: He’s 28 until he becomes 29. That’s how it works
PA: Perhaps if you had paid more attention in Maths lessons? You might remember “round up or down to the nearest whole number”
G: He’s 28. That’s a fact.
PA: No, it is not. £1.75 is not one pound. You don’t even understand what a fact is now.
G: Until he is 29, he is 28.

When it is the next day after your birth, are you 1 day old? technically you could just be a minute old but claim you are 1 day old.

My instinct to perform mathematics on dates would be to use an existing date library. Another developer tried to make something themselves. This seemed a bit complex to me, but I think it actually worked, or at least seemed reasonable for how they wanted to use it.


public static double AgeInYearsAtDate(DateTime effectiveDate, DateTime dateOfBirth)
{
        double daysInYear = 365.25;
        int completeYears = Age.GetYears(dateOfBirth, effectiveDate);

        dateOfBirth = dateOfBirth.AddYears(completeYears);

        double proportion = effectiveDate == dateOfBirth ? 0 : Age.GetDays(dateOfBirth, effectiveDate) / daysInYear;

        return completeYears + proportion;
        }

        public static string ConvertCurrentAgeToYearsAndMonths(double age)
        {
                int monthsInYear = 12;
                int years = (int)age;
                int months = (int)Math.Round((age - (int)age) * monthsInYear);

        return $"{years} year{(years == 1 ? String.Empty : "s")} and {months} month{(months == 1 ? String.Empty : "s")}";
        }

Ages Part 2

Another developer was testing his age code and wrote this:

new object[]
            {
                new DateTime(2010, 05, 31),
                new DateTime(2009, 06, 01),
                AgeRange.UpToOneYear,
                "52 weeks and 0 days"
            },

If there’s 52 weeks in a year, then is that 52 weeks? kinda looks 1 day short to me. Time is mental isn’t it?

Although Junior developers can be useful, I have been against my employer’s over-reliance on them. If you get someone cheap with high potential, as long as you reward them, you end up with someone that knows your system, loves the company and is a great developer.

The problem is that we love hiring them but not rewarding them which means the best ones leave and the bad ones remain. The focus on cheap wages has led to more and more offshoring which has led to the rapid expansion of our Indian office. How do you hire so many people quickly? lower the standards. So now you have a high amount of incompetent people but they are cheap.

It’s not the fact they are Indian that is the problem, it is the fact the demand is high and the standard we had in hiring is low. The problem this has in the work culture is that it is easy to see a discrepancy in quality between the UK and Indian developers as a whole; which means you end up seeing them as inferior, despite some of them actually being good. The good ones tend to be the ones we hired in Senior positions, so they would naturally have higher wages anyway.

So building on from my recent blog on one particular developer, Here’s a collection of things other people have done:

Rollbacks

James has just rolled back someone’s changes who merged into the wrong folders.Don’t they think something isn’t right when it is showing [add] next to the main Database folder. Looks like they copied the folders up one level so now it is re-adding everything as a duplicate.

Dean 16:27:
haha
Me 16:28:
that change by Portia is mad when you look at the changesets
original patch
change to patch, 
fix db patching errors, 
rollback, 
rollback other changes,
rollback from xml file,
then Chris comes into undo the rollback
Dean 16:30:
it's just wrong that we've got people who don't know what they're doing
Me 16:30:
but it's cheap
Portia went wild on that second “rollback” and manually reverted the files.
removed 8 patches and added 1, instead of removing 1
it's amazing how many rollbacks happen these days
Dean  16:40:
Rollbacks worry me in general

“used for identification”

In general, SQL databases are designed to reduce redundancy. So if you have a table storing a list of “job roles”, then if another table references this information, you can link it together via an ID of the row. What you shouldn’t do is copy the data into another table. This means if the data needs to be updated, then you need to remember to update both, and this will double the storage space too.

I saw that a developer was doing this. It was only one column of text, but why were they copying it over into their new table instead of just referencing it?

Me
Is there a reason why this isn't being taken from JobCategory?
It is never returned in a stored proc call so there is no need for it

Vignesh
JobCategoryName used for identification of JobCategoryID and not used in stored proc. Thanks

Me
Regardless if the system uses the data, or if it is there for our Staff to read in the database; you would just write a query that joins onto the JobCategory table.
what if the JobCategoryName in JobCategory is updated? The names in your new table won't be accurate

Vignesh
JogCategoryID only used in stored proc/code, JobCategoryName is just an identification for JogCategoryID in the table. Thanks.

Me
So it needs to be removed?

Vignesh
JobCategoryName was removed since it is used in code or stored proc. Thanks.

Refresh Link

private void llbl_RefreshList_LinkClicked(Object sender, LinkLabelLinkClickedEventArgs e)
{
IEnumerable<ExecutionScheduleDetail> runningItems = _service.GetAllScheduleSearches(AuthenticatedUser.Organisation.Guid);
int count = (from runningitem in runningItems select runningitem).Count();
if (count>0)
{
LoadRunningSearches();
}
else
{
MessageBox.Show(
"This run has just completed and details can no longer be viewed.",
"Running Searches",
MessageBoxButtons.OK,
MessageBoxIcon.Error);
LoadRunningSearches();
}
 
}

Instead of just getting the count from the Ienumerable, they are selecting all the items they already have. Then since they are calling the LoadRunningSearches method in both parts of the IF, it may as well be moved out. So then the code would just be

if count == 0 , show message box.

when a review comment was left about not specifying the method call twice, he then just moved the GetAllScheduleSearches to a field, which meant it would no longer get the latest searches every time you clicked. Since the link is to “Refresh”, it wasn’t doing what it was supposed to.

If Constraint Exists

 if exists (Select * from sys.check_constraints where name = 'DF_Templates_AgeRange_AgeTo ')
 alter table Templates.AgeRange drop constraint DF_Templates_AgeRange_AgeTo;

I noticed there was a redundant space at the end of the constraint name so I thought it was likely that the check would never be true (unless SQL ignores it automatically?)

Me 4/28/2022
Is this space intentional?    
Vignesh 4/28/2022
Removed
     Joel 4/28/2022
Do you actually need the select check? I think you should be able to use the dependent patch mechanism instead.
     Vignesh 4/28/2022
I think it is not needed, we checked the condition to avoid any error. if its true it will execute
     Joel 4/28/2022
The constraint is added in patch 7.809, on which you've marked this patch as dependent. So this patch will literally only run if the constraint was created successfully.

We have an attribute in the xml so you can state dependent patches, so will only run if the prerequisite patch has run. Vignesh was aware of it because he had used it, but then he also had this guard clause that possibly didn’t even work.

When told he didn’t need it, he then agrees that it isn’t needed, yet, put it in there so it would “avoid error”. Does he mean there was an error? Or just being overly cautious?

Spelling

inActive ? ResourceStatus.Inactive : ResourceStatus.Active

Sometimes, it’s the little things like this that annoy me. How can you write “inActive”, and not realise that you either:

have spelt “inactive” wrong,
or alternatively – someone else has when they created this enum

Therefore why did they not fix it? There’s clearly an inconsistency there.

In a similar fashion, I saw this recently:

//Recieved and Transalted

Both words are spelt wrong. It was also copy and pasted from another file. It does pose a good question though, if you copy and paste, do you think you should correct the spelling or leave it for maximum laziness? I guess the advantage is if you search for that text to try and find the original code, it’s better to match it as much as possible.

throw new NotSupportedException("Can't able to fetch template consultation details!");

Indians always seem to write “Can able” and “Can’t able” instead of just “can” and “unable”.

Untested code

string.Format("{0} {1}", _isRegistered ? "Not Registered:" : "Registered:", statusCode)

The logic was consistently backwards. It wasn’t a case that they typed it wrong and didn’t bother testing it. There were several files with the same type of logic. I pointed it out and they rewrote the entire thing.

Month: Dec 2024

Time