There are a number of Java libraries for data synchronizing/replication. Two that I’m aware of are daffodil and SymmetricDS. In a previous life I foolishly implemented (in Java) my own data replication process. It seems like the sort of thing that should be fairly straightforward, but if the data can be updated in multiple places … Read more
I had a similar problem. I decided to use a purely JSON in and out approach. The solution I’m taking on form submission is: catch the form submit event check whether or not the user is online if user is online then submit the form as normal form POST if user is offline then stringify … Read more
First, let me introduce some terminology. A critical section (CS) is a sequence of instructions that can be executed by at most one process at the same time. When using critical sections, the code can be broken down into the following sections: // Some arbitrary code (such as initialization). EnterCriticalSection(cs); // The code that constitutes … Read more
The first thing you have to decide is a general policy about which side is considered “authoritative” in case of conflicting changes. I.e.: suppose Record #125 is changed on the server on January 5th at 10pm and the same record is changed on one of the phones (let’s call it Client A) on January 5th … Read more
I created a small JS lib named WebSqlSync to synchronize a local WebSql DB with a server (client <-> server). Very easy to use and to integrate in your code : https://github.com/orbitaloop/WebSqlSync The open source project QuickConnect contains a JS library to synchronize the local HTML5 SQLite DB to a server DB (MySQL or other) … Read more
You should look at how distributed change management works. Look at SVN, CVS and other repositories that manage deltas work. You have several use cases. Synchronize changes. Your change-log (or delta history) approach looks good for this. Clients send their deltas to the server; server consolidates and distributes the deltas to the clients. This is … Read more
I’ve done something similar to what you’re trying to do. Let me tell you what I’ve learned and how I did it. I assume you have a one-to-one relationship between your Core Data object and the model (or db schema) on the server. You simply want to keep the server contents in sync with the … Read more