trying to search how to use 'createSyncTable' in SQLite but couldn't find anything about it. Can someone provide some detail on what is it and how to use it? I am building an offline app that will time to time sync data with the server. If this table handles synchronization that it would make it a lot easier.
Thanks
Related
I was thinking of making an app which plays a specific set of small audio files stored away in a firebase database, or any other database on the cloud.
The number of files may exceed hundreds, so wrapping all the files in the app might not be the best of ideas.
I'd really like to know how to go about this problem.
Downloading only the required file from firebase when it's clicked and playing as its being downloaded all the while caching it for future playback seems plausible, but I'm not quite sure how to implement it.
I'd appreciate a few pointers towards this, thanks
Yes. You are thinking in the right direction.
You might use these things.
App UI - Ionic2 will provide you a very nice and easy to implement platform to create a UI. Please refer this documentation for the basics and details about using Ionic2.
Local Storage - You can use this to store downloaded files. In any app where data is relatively large, using local storage is the smart choice. This helps you reducing the size of the initial app to be installed and download the content as and when needed.
A well defined database - Now, whether to use non-structured (No-SQL) or structured (SQL) is the first choice you have to make.
If it's just content - audio files download and play with no complex cross querying the database, then you can choose to use non-structured (No-SQL) database like Firebase database.
But, if you have good requirements for structuring data, query it with constraints like "Give me all the audio files list where a particular user has played it in last 10 days" or "Give me all the users who has played/downloaded a particular audio file more than 10 times" and so on, then you better use structured (SQL) database like PostgreSQL.
RxJS - Now, this might not be very important to do, but, if you use this from the start, it's a good choice. Advantages are, e.g. you might not have to wait for all the file to get downloaded before playing it. Use Observables and Promises for such a mechanism.
Could help with the specifics when needed. Hope this helps. :)
I am just trying to use flyway for the first time. So I put relevant clarifications as one post here. Please apologize. Am trying to make our two development test dbs (oracle) as sync or maintained with version. I have below clarifications on that.
1.Practically we have around 4000 objects in our db. Is this tool compatible and fast enough to handle this many objects?
We don't want to maintain data level version control for all the tables. For examples for transaction tables we don't want to sync production and development. Rather some configuration tables or master tables data needs to be maintained. Is it possible?
Let us by assume example db1 will be considered here as production and db2 will be considered as development. For that should we have to generate a SQL script manually that includes the entire DDL and all tables dml for db1? or flyway has command/option to do that?
Please clarify the above questions or guide me any documentation to refer to try in test set up to familiarize before to implement in actual project.
Thanks in Advance
Balaji
currently I am writing a Windows 8 App with Sqlite as a database. I want to give the user the ability to view his data in every instance of the app on any device. Usually this problem could be easily solved by using a online database like Windows Azure. But this is not an option in my case.
Is it a good idea to use Microsoft's free service "Skydrive" as a platform to synchronize database files among several devices? Does somebody know any open source projects or blogs that are dealing with this problem that could save me some time for writing the necessary code?
If it's a bad idea, which other options are there that I could use. I want to keep Sqlite as the database for my App.
I am glad to get any kind of feedback or links to resources that might help me.
Best regards
Philipp
imo it isn't a good idea cause the access to db files is to easy. Ofc you can say that access to database files is easy cause you need to just know the app data path to package of your app but still it`s much more difficult than just opening skydrive. And think what would happen if someone would make this directory on skydrive as public.
I would combine local db and online db. Online db as a service for synchronizing data and local db for normal work.
I'm wanting to build up a pre-filled sqlite database using Django as a front-end data entry inputter; however I've read this site and on StackOverflow that isn't that easy to do; and one needs to use CSV files.
That's fine if your database is pretty small - but what if you're pre-filling it with data that has relationships (ie: Customers, Orders, Salespeople, etc); or if the database you're building requires a lot of data input (1,000+ records).
My app/database will be pretty big and have a lot of pre-filled data with multiple references/relationships -- I really don't want to re-enter all this stuff into CSV files or into the Simulator and I thought using Django would be a really quick and dirty way of getting vast amounts of related data into an iphone app.
This kinda raises the question of whether Core Data is really worth it, the learning curve is really high, the syntax can be cumbersome and I'm considering just using FMDatabase, except I can't get the LIMIT/OFFSET to display rows of data in batches correctly (any help or hints on tips how to do this would be great!).
Therefore, if you're wanting to pre-fill a database using Core Data and a large database what is the best route forward?
You might want to have a look at the Active Record port for cocoa/cocoa touch. I've done an app like this before, and what we (the client and i), choose to do was to import the data from an XML file on the first app launch. The idea being that as the parser was built into the app, we could do OVA updates if we choose to at a later date. The data did have fairly complex relationships, but i decided Core Data was still the way forward.
I've only used raw SQLite once, and that was before we had CoreData on the iPhone. Also you should consider what your solution is for doing schema migrations which are handled by CoreData.
A Hybrid solution is to load the data into Core Data in the simulator, and then ship that SQLite database with the app, and copy it into the app's document directory, on the initial load. Best of both worlds.
Good luck
I'm wondering how SQLite implements it. Is it based on file-locking? Surely the entire DB isn't locked for every user that accesses it; that would be extremely inefficient. Is it based on multiple files or just one big file?
Would be nice if someone could give a short overview of how synchronization and locking is done in sqlite, or, of course, provide a link to one.
Have a look at the SQL Lite FAQ and this on locking. Hope this helps.