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XML vs JSON vs SQLite for only reading data

I have a collection of 350 locations in the United States with each containing about 25 subcategories. The data structure looks something like this:
Location (ex: Albany, NY)
--> Things to do
--> Population
... 23 More
Which of the following would be best for loading this data into the app: JSON, XML, or SQLite? Just to clarify, I don't need to edit this data in any way. I simply need to read it so that the information can be loaded into TextView's.
Edit:
I'm attempting to implement Room and XML and so far the XML seems to be the simplest to implement. Is it bad practice to use the XML solution? It doesn't seem to be using too many resources and it isn't running slow at all when tested on a few devices. Would it still be a better practice to implement the Room solution?

Undoubtedly, among all of these RDB is the most efficient one, both in terms of storage and query response. I personally do not see any point in using xml and json as these have been traditionally used for exchange of data and are inefficient for storage and queries.
I would suggest that you evaluate the following:
a) how are you going to store the data: single file vs multiple files(for example by subject)
b) are you going to be doing updates on the strings or just appending(SQL will be better suited for updates but if it just reading data after a batch processing flat files might be better suited)
c) How complex are the queries that you want to implement.XML and SQL are better suited for queries that might try to address metadata (date stored, original location address, etc.) than JSON
Once you determine what you want to optimize: whether it is on adding metadata, fast updates, fast querying, ease of storage, fast retrieval of subject files, etc. then you can decide the tradeoffs with other less important goals. In this specific instance the devil is very much in the details.

In most cases it would be better to use a database because it increases readability and maintainability. Especially if you want to show these information inside a kind of list-view. If you use JSON or XML you'll have to parse or write a lot of code to switch between things or load them with a good performance. Consider the case of using Room, LiveData and a RecyclerView, this will reduce the code you'll need and improve( a lot) performance and readability of your app code. By the way you should provide more information about how you want to use and where you want to show these information. XML (or the Android resource system) should be used if you plan to use the resource system itself with its qualifiers to reduce your work. Most of the time JSON is used to communicate outside or with another app in an easy way or for REST requests/responses.

The one option that wouldn't make sense to use at all for your use case is SQLite. Unless you plan on running specific queries on the data for preprocessing before loading them into your view it doesn't worth the overhead (even if I don't imagine is a lot with 350 locations)
XML vs JSON serve the same usecase without much difference, read up their specifics in this website: https://www.json.org/xml.html
I would personally go for JSON due to the simplicity of the format.
Edit:
#simo-r Argument is also a valid one in regards to readability of your code. While there are libraries that can make reading json/xml easier by default Android has really good SQLite support so it might make sense to use it. Ultimately it is in your personal preference and where you see the project growing.

I have a collection of 350 locations in the United States with each containing about 25 subcategories.
The main issue is scalability
Will you, in the next few years, keep just a few hundred locations, or do you imagine, that, if your software becomes successful, your data would grow to many thousands of locations?
If yes: choose SQLite because it could store many records, in an efficient way. Don't forget to have a good database schema with appropriate indexes. See this and read about database normalization. Also, an SQLite database could later be migrated (with efforts) to PostGreSQL.
If no (your data has just a few megabytes): keep JSON or XML. The data is in the page cache.
Consider also YAML, and sometimes a mixed approach.
don't forget to document how your data is organized and accessed.
See also the data persistence chapter of this draft report

If you gonna simply bind data into text views, you can just store the text as strings.xml. As simple as that.

Go with JSON.
Advantages :
Low overhead ( Vs SQLite )
Lightweight parsers like Jackson available using which you can easily convert your data into custom object or data-structure if you need.
Maintainable. As most of the developers understand the format.

I would suggest using JSON. Reason below
JSON vs XML
JSON is lightweight than XML and would take fewer resources(network and storage). Performance of the app increases.
JSON parsing is easy and as mentioned above, its trivial.
JSON is friendly to javascript, in case it's required.
JSON vs SQLite
350 data set with 23 attributes, can be easily managed by JSON. RDBMS is not required.
SQLite becomes an overhead. It's an extra layer and layer comes with a cost. Especially if the application is containerized, the architecture becomes complicated. One needs to deal with volume mapping etc, in case of JSON you can keep the data as part of the application code.
Importantly, since data is static, keep the application stateless by keeping the data alongside the codebase. This makes lot more sense from architectural perspective.

Problem
You have a fixed set of information with a simple structure that you wish to deliver to clients.
Questions to Reflect On
Do I expect this information to significantly changed or modified ever?
Do I expect to increase the amount of information available?
What kind of help do I have? Do they have a background in software engineering or is it someone of a different profession that has to wear a lot of hats?
What is the scale of the project? Are you expecting a large amount of users or just people interested in a very niche application?
JSON or XML
JSON and XML provide similar services: they are both data transfer protocols. If the information is not expected to grow both might be a great option. If its public information, just serve these files statically over nginx. You can point a worker with limited software engineering experience to update these files; they're just files in a folder presented in a human readable format... its extremely simple to do. These updates should be minor and infrequent.
JavaScript Object Notation(JSON) Pros
solid browser and backend support
small size and fast parsing by the javascript engine
very human readable, easy for the untrained eye to make changes
Extensible Markup Language(XML) Pros
standard meta-data option
supports namespaces
solid backend support and is often baked into frameworks
This article explains XML and JSON differences really well (in 2020) if these highlights were not sufficient for your investigation.
Database System
There are a plethora of database systems out there. Their job is to efficiently retrieve specific information from a large volume of data stored. The key reason to use databases is scalability. Scalability means a number of things; I view it as adapting to drastic change. If you expect this information to frequently change or grow, go with a database.
Object Relational Mapping (ORM)
Databases can be cumbersome to use. I would recommend using an ORM on top of them. These encapsulate a database and makes it more user friendly (language specific). Room makes sense in your use case especially for java android development. Encapsulation also allows you to migrate to other databases later without change your code. Here's a good article that discusses Room and SQLite!
Miscellaneous
"Is it bad practice to use an XML solution?"
No. The important thing is that it works, is understandable, and runs efficiently. Just keep in mind that XML and JSON are data transfer protocols and they do THAT job well. This stackoverflow discussion may be helpful to gain a better picture of what that means; be sure to read more than just the accepted answer.
"It doesn't seem to be using too many resources and it isn't running slow at all when tested on a few devices."
Although testing for functionality is great, keep in mind that your test is not a load test and does not verify what you're trying to confirm. I would explore load testing, Wikipedia is a good place to start!

Apache Solr, SolrJ vs Data Import Handler for parsing XML

I'm hoping to use Solr to run searches from info parsed from XML files.
These XML files are not in Solr's document format, as such I have to parse them and get the fields I need that way.
I am familiar with Java programming and was wondering if SolrJ would be an easier method than using the Data Import Handler. I'm considering running through each XML file I have and parsing the fields that I need from each. Is there any downside to one method over the other? I imagine since I have familiarity with Java it may be easier to parse the XML that way?
I will probably need multiple conditions and regular expressions. If anything, a reliable way to get my fields from relatively unstructured XML.
How would SolrJ work with the interface? That is, if I index using SolrJ, can I do my queries through the interface still?

DIH was designed for prototyping, though some people do use it for production. You can start from it, but be ready to jump to SolrJ or other methods if you hit its limitations. And if you have very complex mappings, you may be better off with SolrJ to start from.
You can also apply XSLT transform on an incoming XML document to map it to the Solr format.
And as said elsewhere, search is a separate issue from indexing.

How you index your content into Solr is orthogonal to how you query it. You can index any way you want, as long as it produces the right docs in the index.
Now, regarding indexing, if DIH will get what you need without much tweaking go for it. But if you need to do a lot of tweaking of the data, in the end you might finish faster if you just write some java with Solr. With Solr you have all the flexibility, with DIH you are more constrained (think of the 80/20 rule).

Neo4j: Enforcing schema with XSD

I was wondering if there exists a tool for Neo4j that can read an XSD file and use it to enforce a schema on Neo4j.
I'm newbie on graph databases but I'm starting to appreciate the schema-less approach. There's a lot of projects out there that have been pumping in a lot of non-sequential data and making sense of it all which is really cool.
I've come across some requirements that call for control on what properties a node or edge can have given a certain label and what labels an edge can have given the labels of its source and destination nodes. The schema is also subject to change - although not frequent.
As I understand, the standard practice is to control the schema from the application itself which to me doesn't seem like it should be a BEST practice. For example, the picky developers from Oracle land create views for applications to interact with and then apply triggers onto the views that execute the appropriate transactions upon the application attempting to insert or update on the view.
I would be looking for a similar device in Neo4j and since I already have the XSD files, it would be a lot less work overall to simply dump them into a folder and have it use those for reference on what to enforce.
This is something I'm willing to write myself unless there's already a library out there for this. I have a day job after all. :)
Thanks!

Not only does this tool not exist, but it couldn't even exist without more work on standardizing how XML is stored in neo4j. There are key differences between the XML model and the neo4j model.
There's this python application here that can import XML into neo4j; documents, not schemas. But in the way that it does it, there are many things to keep in mind:
There's no obvious mapping from XML elements/attributes on to neo4j nodes/properties. You'd think that elements should be nodes, attributes properties; but a better graph model would usually be different than that. For example, XML namespaces would make great nodes because they connect to so many other things (e.g. all elements defined in a namespace) yet typically they're attributes. Maybe namespaces should be labels? Also maybe a reasonable choice, except there's no standard answer there.
XML trees have sequence, and sequence matters; graphs don't. Say you have an XML element with 2 children, A and B. In neo4j you might have a node connected to two other nodes, but you need a way of expressing (probably via a relationship property) that A comes before B. That's of course doable in neo4j, but there's no agreement as far as I know about how to do that. So maybe you pick a sequence attribute, and give it an integer value. Seems reasonable...but now your schema validation software has a dependency on that design choice. XML in neo4j stored any other way won't validate.
There's a host of XML processing options that matter in schema validation that wouldn't in a graph, for example whether or not you care about ignoring whitespace nodes, strict vs. lax schema validation, and so on.
Look, neo4j is great but if you really need to validate a pile of XML documents, it's probably not your best choice because of some mismatches between the graph model and XML's document model. Possible options might be to validate the documents before they go into neo4j, or just to come up with a way of synthesizing XML documents from what is in neo4j, and then validating that result once it's outside of the graph database, as an XML file.

XML as data store. Insert, remove, delete

I was planning to use XML to store the data for a Java DVD database application I'm writing. I know that the word "database" is right there in the title, but XML just seemed so much more portable, was human readable and (I assumed before looking into it) simpler to implement.
Parsing XML seems to be the easiest thing in the world... even creating a new XML file isn't much trouble, but changing records, inserting them or deleting them, I can only see to do by creating a fresh XML file.
Am I missing something? Or is the thing that I'm missing that I should switch over to a database format (but there's some wonderful database format I've not heard of, that's totally portable and users won't need to install something separate to use :) )

the most popular way to use a file as a database is probably with sqlite http://www.sqlite.org/ and that's what i would use if i were solving your problem (it's pretty much a standard SQL database, but uses just one file as storage). another, pure-java option is apache derby http://db.apache.org/derby/
however, pure xml databases do exist (and were quite fashionable about 10 years ago - the "nosql" of their time) - the associated standards are xpath http://en.wikipedia.org/wiki/XPath and xquery http://en.wikipedia.org/wiki/Xquery . i haven't used it, but it seems like basex http://basex.org/open-source/ is an open-source implementation that you could use (and it does claim to provide ACID guarantees - http://basex.org/products/ ).
if you're more familiar with xml than sql i don't see any great harm in using an xml database for a small project. just structure your code so that most of the program doesn't care what the storage is (ie by providing a neutral interface). then if xml doesn't work out you can switch to sql by re-implementing just that interface and leaving the rest of your program alone (and if it does work, post back here saying so - it would be interesting to know).

If you're going to have a web-based front end, it seems that a regular database is the way to go as the back end. I don't believe your users would have a need to download anything new, since that's all taken care of server-side. A real database also has the ACID advantage over a pseudobase; it should be atomic, consistent, isolated, and durable, and I can't imagine XML would be a good substitute in those respects.

Suggest a persistent strategy for a workflow system

I am in the process of creating a UI configuration tool for my pet project. One aspect of this tool lets the end user DEFINE his orchestration. I then need to save this orchestration definition into a database. There will be a executable version of this definition in a running system. The executable version is created dynamically on-demand.
Idea is to separate the DEFINITION from EXECUTABLE version so that I have the flexibility to choose the runtime version among BPMN or JPDL or a POJO based workflow solution (BeanFlow).
Limitation: I can't use the BPMN editors that come with frameworks like jBPM, Activiti etc as I wan't to use my own UI that is specific to my domain.
I need suggestions on HOW to PERSIST the definition.
Should I use rdbms tables? If so, is there a db schema I can borrow that is close to orchestration concepts?
Should I serialize my definition to BPMN/JPDL XML instance document?
Are there any other simple formats that I can use?

By "orchestration" I'm assuming you mean a finite state machine. Where the current state dictates what transitions can be followed to other states. The representation of states and transitions as edges and vertices often produces a directed acyclic graph, however there are times when the graph will cycle (e.g. draft -- submit for approval --> pending approval -- reject --> draft).
In practice, separating the definition from execution calls for a persistence format that can easily accommodate customization. As your system evolves you will find a number of unanticipated edge cases whose solution should not require altering a persistence schema, only code. This implies XML or a NoSQL solution - something whose schema is easily changed or non existent.
Now, having written my own XML definition for this purpose (for uninteresting reasons I'll exclude), my suggestion is using JPDL (or BPMN). Reason is their definitions likely incorporate whatever you're considering now, will in the future, and enable customization - such as hanging arbitrary data or behavior off them at a given point. You also get the advantage of tools already built - not just UI - for dealing with cycle detection and ensuring there is a path to completion for example.
Some of the interesting features I know JPDL possesses are an ability to help merge forked processes, timed tasks (including those that repeat periodically), and facilities for sending notification. This last item - notification - bears some further exposition. One of the things I've found with my own system is the need for sending out configurable email whose content is based on the data flowing through. These existing engines make that relatively easy by providing a way to plugin variables for instance into text that's then dynamically evaluated at run time before transmission. Also they provide bridges between the engine and whatever user store for the purpose of sending notifications to groups of people, tasking them and enforcing security policy.
Finally, depending on the scope of your system, you will probably still be using a database as well. What I suggest is storing off the XML and data being orchestrated into the database in a serialized format. Then, if the data is being altered as it travels through the execution, write out serializations of the data - and perhaps workflow if it is also changed - into a history/audit log table as well.

I would NOT use rdbms tables, or if you do, store the definitions as text blobs. Trying to make records for the definition is a bad idea because it's much more inflexible and difficult to change your definition over time. Many people would use different approaches, but I'd use JSON or YAML, and avoid XML. The motivation for that is to make it as simple as possible. Trying to use XML, especially a formalized specific format of XML is going to make you spend much more time meeting an exact specification that doesn't actually do anything to help what you're trying to accomplish. JSON and YAML are both very easy to work with from a code perspective. YAML is more easily readable by humans and easier to edit, and isn't as tricky for punctuation and escaping as JSON. JSON is more widely used, and is smaller than YAML. JSON also has a binary counterpart, BSON, if document size is a concern.
Once you have an importer/exporter that goes to/from your internal objects to your data format, then persisting using RDBMS, or other mechanisms, will be straightforward. You could even use CouchDB, which could offer other benefits to your application and may be a great fit.

Very good question! Here is my two cents:
RDBMS: if you do this you will be able to query the workflow instances, for example which tokens are at 'node X'?
Storing XML as clob: the simplicity is the truth of this solution, but you can't really query these just get them by id
NOSQL: there are a lot of different solutions for different problems. MongoDB is a popular solution, it provides document oriented persistence.

How about a simple serialisation of the composed UI using for example XStream and then store the serialised bits into the database as a binary column. Then when user logs in, get the associated data, deserialise, initialise if required and display.