OMS Pro: Understanding Data in TrackVia (TrackVia 101)
The Basics: How Does TrackVia Store Information?
If you find yourself needing to figure out how to troubleshoot or update something in the system, the first step to understanding how to change it is to forget whatever it is you think of when someone says "OMS" or "TrackVia" to you. The flows, text fields, and dropdowns you use in TrackVia on a day-to-day basis are almost all just Forms. When it comes to working with TrackVia, you'll need to think about what's going on behind the Forms.
Tables Are Where It's At
At the end of the day, TrackVia is just a bunch of fancy spreadsheets. Each spreadsheet, in TrackVia terms, is called a Table. For instance, in OMS Pro, there is a Table called "Location/Facility", which is really just a spreadsheet of every location a customer has ever given us.

Looks familiar, right?

As illustrated in the very generic image of a spreadsheet above, the TrackVia Table also has columns (Fields) and rows (Records). Each Table is just a whole bunch of Records with information in every field that tells us what we need to know about those Records. In this case, the Location/Facility Table is filled with Location/Facility Records - we have fields that prompt us to keep track of every Location/Facility's name, the customer associated with it, its tax rates, what type of property it is, and much, much more.
But what if you don't need this much information? What if you'd rather just see the certain Fields, or even filter out some of these Records - say you only wanted to see the ones that are near the Anderson office. That's where Views come in!
Views (for When The Whole Table Is Just Too Much)
A View is just a custom way to look at the information in the Table. A Table can have an unlimited number of Views that are all doing different things. The "Default View" will display all of the Fields (columns) and all of the Records (rows) that exist in that Table. To see the available Views, click the black triangle to the left of the name of the View you are currently looking at (in the screenshot above, it's the Default View for the Location/Facility Table, so it just says "Location/Facility") and select another View from the dropdown.
Views That Filter By Field (Column)
Perhaps you only want to see a View that shows you the the Facility Name and Full Address, like this one:

Based on the name "Quote Assistant - Search Location", it can be surmised that this View was created to make it easier to search for a unique Location/Facility Record by address or name: since it only displays the Facility Name and the Full Address, if you search within this View for something like "St. Andrews", it won't show you Location/Facility Records that were recently updated by someone with the name Andrew, or are linked to a Customer named Andrew. By limiting the number of Fields you are working with, a View can save a lot of time on repeat tasks (and save you a lot of side-scrolling)!
Views That Filter By Record (Row)
What if, instead of (or in addition to) limiting how many different Fields are included on your screen, you want to filter out Records that don't meet certain parameters? This can be done by adding a Filter to the new View. Take, for example, this View, "Anderson County Locations".

The Filter associated with this View checks every single Location/Facility Record, and only lets them through to this View if the phrase "Anderson County" is present in the Field "Link to Complex". It also only displays the Fields that are relevant to the task for which this View was created.
Figuring Out What A View Is Doing
If you're looking at a View in TrackVia, you can check whether it includes absolutely every possible Field and Record in the Table (a.k.a. the Default View) by clicking that same dropdown at the top left. If the View you're currently looking at doesn't show up in that dropdown with "[Default View]" next to it, the only way to see absolutely everything the current Table has to offer is to swap over to that Default View. Frankly, there's no reason for a View other than the Default View to exist if it has the exact same information as the Default View.
You can check what Fields a View is omitting by clicking the three horizontal bars at the top left of the View (the "hamburger menu") and selecting "Edit This View". The popup window will show you what Fields have been "included" on the right, and what Fields are still "available" on the left - i.e. you aren't seeing the information in those Fields on this View.
Fun Fact: if one of the Fields on this Table is used to Link a Record in this Table to a Record in another Table, you can actually add any of the Fields on that other Table to a View on this Table! While in Edit This View mode, you can see which Tables are Linked to the current Table in the "Selected Table" dropdown. For example, each Record in the Location/Facility Table is Linked to a Record in the Customers Table - that may be the property owner, the management company, or whoever requested we work at that building. Having access to the Linked Customer means that you could actually have a View on the Location/Facility Table that includes Fields from the Customer Table: just by opening up a random Location/Facility Record in the right View, you could see whether the Customer who owns that Location is tax exempt, for example, or any of the other information we keep on them, without having to look the Customer up separately in the Customer Table!
To see which Records are excluded from your current View, use the same hamburger menu dropdown and select "Edit Current Filter". The "Filter Settings" pane will show you a list of conditions that must be met for a Record to be displayed in the current View. For example, the Anderson County Locations View mentioned above:

Sometimes there will be a Filter with multiple conditions listed in the same bracket. In this case, having the word "AND" selected in the dropdown shown in the above screenshot will mean that all of the conditions listed must be met, whereas swapping it out for "OR" will mean at least one of the conditions in the list must be met for the Record to be displayed within the View that uses this Filter.

Lastly, a View can also have a specified Sort Order saved to it. The Records that display in a View can be sorted by any of their Fields, either ascending or descending. If you're looking at a View and you notice that the "Sort" button is all green (selected) and shows a number in parentheses, you know that the current View is showing you Records in a certain order. If the number in parentheses is greater than one, then the Records are being sorted by more than one Field. You can see what Fields and what order the Records are being sorted by simply by clicking that Sort button.
So If TrackVia Stores Info In Tables, and Tables Are Displayed In Views... What's A Form?
A Form is just a prettier way to look at (and interact with) one individual Record, in the same way that a View is a prettier way to look at a Table. If you click on any Record in a Table, it will display in a Form that helps you understand the information you're looking at, and sometimes even helps prompt you on how you're meant to interact with it.
For example, opening a Record in the Location/Facility Table gets me this:

Along the top, you can see that I am currently looking at this Record in the "Location and Facility Overview" Form, which is a Form created for the Location/Facility Table. If I don't like using this Form, or if it's excluding some information from the Record that I need (the same way that Views might exclude information from the Table that I need), I can click on "Location and Facility Overview", the name of the current Form, at the top of the page, and it will show me a dropdown of all available Forms.
Just like with Views, the only way to be certain that I am looking at all of the information available on this Record is to use the Default Form. It's nowhere near as pretty as all the nice interactive Forms most people work with in OMS, but it's guaranteed to be complete.

If you need to understand a Form better - what Fields it's including or excluding, for instance - you can use the same hamburger menu in the top right corner and choose "Edit Form", just like you did with the Views. (This won't work on the Default Form.) From the Edit Form page, you'll see a list of available Fields, including Fields from Linked Tables, just like on the View level, that you can include in this Form if you wish to edit it.
Review
So those are the most basic building blocks of TrackVia! All of OMS is made up of Tables, which are filled with Records that have certain Fields of information. You can curate what parts of a Table you see with a View (and you can apply Filters to a View), and you can curate what parts of a Record you see using a Form. In some cases, a Field might exist that lets you can Link a Record in one Table to a Record in another Table, which gives these two Records access to each others' information.
So What's The Big Deal?
Most of the "logic" that TrackVia does happens within the Table itself - certain Fields may auto-populate information into other Fields, or there may be some custom code (an App Script) saved to the Table that changes things around based on user input. If you are trying to solve an issue within OMS, however, the first thing to do is determine whether the issue is coming from the Form (is the information showing up for the user correctly?), the View (is the information being filtered from the Table correctly?), or the Table (is information getting saved into OMS correctly?).