I try to write a quick and simple list of common use cases, because as @rmaddy says this answer could fill a book chapter: NSUserDefaults: stores simple user preferences, nothing too complex or secure. If your app has a setting page with a few switches, you could save the data here. Keychain (see SSKeychain for … Read more
Use the pickle module. import pickle d = { “abc” : [1, 2, 3], “qwerty” : [4,5,6] } afile = open(r’C:\d.pkl’, ‘wb’) pickle.dump(d, afile) afile.close() #reload object from file file2 = open(r’C:\d.pkl’, ‘rb’) new_d = pickle.load(file2) file2.close() #print dictionary object loaded from file print new_d
When deciding what persistence to use, it’s important to remember that Core Data is first and foremost an object graph management system. It true function is to create the runtime model layer of Model-View-Controller design patterned apps. Persistence is actually a secondary and even optional function of Core Data. The major modeling/persistence concerns are the … Read more
Here are some of the different Ways and Methods to Save data for Unity Projects: Platform-Independent: One way of saving data in Unity3D in a Platform-independent way is to use the PlayerPrefs class. (Learn More 1, 2). PlayerPrefs is a static class and it is very easy to use but not reliable. PERSISTENCE – SAVING … Read more
I’m going to offer something of a dissenting opinion here. JavaFX Properties and JPA As I commented on jewelsea’s answer, using a JavaFX property-based bean with JPA is possible as long as you use “property access” rather than “field access”. The blog post I linked there goes into more detail on this, but the basic … Read more
Probably the exact details of em.flush() are implementation-dependent. In general anyway, JPA providers like Hibernate can cache the SQL instructions they are supposed to send to the database, often until you actually commit the transaction. For example, you call em.persist(), Hibernate remembers it has to make a database INSERT, but does not actually execute the … Read more
You could use this as a rough “ruleset”: YES, use persistent connections, if: There are only few applications/users accessing the database, i.e. you will not result in 200 open (but probably idle) connections, because there are 200 different users shared on the same host. The database is running on another server that you are accessing … Read more
You can’t do it from python, but some clever bash tricks can do something similar. The basic reasoning is this: environment variables exist in a per-process memory space. When a new process is created with fork() it inherits its parent’s environment variables. When you set an environment variable in your shell (e.g. bash) like this: … Read more
As Jon first suggested, you can try creating a mutex. Call CreateMutex. If you get a non-null handle back, then call GetLastError. It will tell you whether you were the one who created the mutex or whether the mutex was already open before (Error_Already_Exists). Note that it is not necessary to acquire ownership of the … Read more