I encountered many troubles of dealing with serializing/deserializing Scala data types to/from JSON objects and then store them to/from MongoDB in BSON form.
1st question: why Play Framework uses JSON why MongoDb uses BSON.
2nd question: If I am not wrong, Javascript does not have readers and writers for serializing/deserializing BSON from MongoDB. How can this happen? Javascript can seamlessly handle JSON, but for BSON I expect it needs some sort of readers and writers.
3rd question: (I read somewhere) why Salat and ReactiveMongo uses different mechanisms to talk to MongoDB.
JSON is a widely used format for transfer data in this days. So pretty good to have it "from the box" in the web framework. That is the reason Play has it.
The same reason mongo use it - it is a good idea to store data in the same format as user query it and save it. So Why mongo use BSON but JSON ? Well, BSON is the same as JSON but have additional properties on every value - data length and data type. The reason of this - when you are looking a lot of data (like db query do) you need to read all the object in JSON to get to another one. We can skip reading in the case if we will know the length of the data.
So You just do not need any BSON readers in JS (it could be somewhere but rarely used) because BSON is format for inside DB usage.
you can read this article for more inforamtion
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I want to use apache avro schema's for data serialization and deserialization.
I want to use it with json encoding.
I want to put several of this serialized objects using different schemas to the same "source" (it's a kafka topic).
When I read it back I have the need to be able to resolve the right schema for the current data entry.
But the serialized data don't have any schema information in it. And to test all possible schema's for compatibility (kind of a duck typing approach) would be pretty unclean and error prone (for data which fits to multiple schemas it would be unclear which one to take)
I'm currently thought about putting the namespace and object name inside the json data programatically. But such a solution would not belong to the avro standard and it would open a new error scenario where it's possible to put the wrong schema namespace and/or object name inside the data.
I'm wondering if there would be a better way. Or if I have a general flaw in my solution.
Background: I want to use it for kafka message but don't want to use the schema registry (don't wan't to have a new single point of failure). I also still want to have KSQL support which is only available for json format or for using avro with the schema registry)
I've inherited some code which makes calls to a web API, and get's a deeply nested (up to eight levels) response.
I've written some code to flatten the structure so that it can be written to .csv files, and a SQL database, for people to consume more easily.
What I'd really like to do though is keep a version of the original response, so that there's a reference of the original structure if I ever want/need it.
I understand that HDF5 is primarily meant to store numerical data. Is there any reason not to use it to dump JSON blobs? It seems a lot easier than setting up a NoSQL database.
It should be fine. It sounds like you'd be storing each JSON response as a HDF5 variable length string. Which is fine, it's just a string to the library.
Do you plan to store each response as a separate dataset? That may be inefficient if you are talking about >1000's of responses.
Alternatively, you can create a 1-d extensible dataset, and just append to it with each response.
Decided it was easier to set up a Mongo database.
Is there a proper way to store generic JSON in MongoDB? With 'generic' I mean any JSON, including hashes with keys that are restricted in MongoDB documents.
For example, we want to store JSON schemas which use the key $ref, which is not allowed in a MongoDB document. This means that a JSON schema as such cannot be stored as a MongoDB document.
Is there a smart way around this? The only options I've come up with is to do back-and-forth deep key replacements or to store it as JSON text.
We're using Morphia, so the solution should be compatible with it.
The solutions you have already thought of are probably the best. Store the schemas as JSON strings then parse them back to JSON on retrieval.
I'm sitting on a CSV import into a database trying to think of ways to add more data without having to change the API (add new fields).
Since working with JSON quite a bit on the client, I'm thinking of storing data into MYSQL as JSON string. So if I have a field
image_filenames
Where I'm currently storing data like this:
img123.jpg
WOuld it make sense to store multiple images in a JSON array like so:
{"img_base":"img123.jpg", "img_alt_1":"img123-1.jpg", "img_alt_2":"img123-2" }
I can deserialize server side, so it woudn't be much of a problem to grab the image I need from the JSON array, while it does not bloat up the API.
Question:
I can't find anything at all on importing CSV with JSON strings. So, what's good and bad in doing so? Are there security concerns (SQL-injections)?
Thanks!
Transferred from comments to here:
If you have a data model scheme that changes or is inconsistent, then the relational database storage isn't the best choice. Sure, you can serialize it and store as binary string, but why? IMO, and I'm not a fan of NoSQLs, but MongoDB looks like something you might make use of. Its document scheme is JSON-based, it'd be familiar to you if you work with JSON-based code on a daily basis. I'd use that to store the data rather than relational db.
Non-relational ones do less work, so they work faster in some scenarios. They also don't have a scheme, so there's no alter table statement as such, therefore you can add "columns" as much as you like. If you don't have relations and need something to store data in JSON format, but that it can be searchable - MongoDB would be great.
Now i am creating Ajax app and i want to know what is better to connect server data with client.
Last time i used json but some time ago i hear that serialized data is faster.
Who know what is better?
In general, a serialized binary representation will be smaller than a JSON representation of the same object (that in turn would be smaller than an XML representation).
In this regards, network transfers would be faster.
Probably you're comparing serialize (working similarly in PHP) and json on your client (a browser). There's a serialize function (similar to how PHP works) in jquery but no native unserialize. I suggest you work with json when communication is between your server and your client (ajax).