i created all the feilds and objects as per the given instruction but again it was showning the error

Hello

Can someone explain when to use different collection types in Apex with some real-life scenarios? 

Some explanation why a certain collection is used would be awesome. (Especially on maps!)

Additionally, are there any collection-specific limitations or best practises which would be good to know?

Thank you!

Hi all!

Question is, is it possible to write a trigger to update a long-text field with data while always keeping the previous data in it as well?

In more detail - whenever a custom-object record is created, then it would update the record related Account text-field with the name, while keeping all the previous names in that field. 
So the field on Account would look like this : Name1, Name2, Name3. 

Thanks!

Anyone having the problem? I was able to login to trailhead yesterday but today when I tried to login, I got the following errors. Really strange I can see my User Id and I think it is not supposed to happen. 

i created all the feilds and objects as per the given instruction but again it was showning the error

I am stuck at "Create a Guest Administrator and deactivate it." I've tried so many different things, but I don't feel the tutorial covers it very well. Perhaps I was supposed to remember it from a previous tutorial, but I must have forgotten. Can someone walk me through it?

Greetings!  My manager (who has the same SF profile as me, and we are both admins) has created a Console App for our Tech Support folks.  I want to edit his app to add a new icon and maybe some functionality, but while I can see the console app in the App Menu area of the Setup, I cannot see it anywhere else and I cannot figure out how to make changes to it.  What permissions am I missing?

Thanks for any help.

I'm having trouble logging into my developer edition when trying to complete Trailhead challenges. Though I'm logged in to Trailhead as a whole, when I click the "Connect to your Developer Edition, it takes me back and forth between the same two screens, over and over again (see attachment). Has anyone else had this problem? What's the solution to get past it? I've done it before, as I have completed trails, points, etc. so I would hate to have to start again.

Hi,

  Can we use the 2-way SSL Mutual authentication as the only authentication needed for the API so that we don’t have to login with UserId and Password?

Thanks in advance.

Hi all!

Question is, is it possible to write a trigger to update a long-text field with data while always keeping the previous data in it as well?

In more detail - whenever a custom-object record is created, then it would update the record related Account text-field with the name, while keeping all the previous names in that field. 
So the field on Account would look like this : Name1, Name2, Name3. 

Thanks!