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Questions tagged [persistent]

Generally in ORM and OOP , a persistent object refers to an object that exists (or persists) in the database

771 questions
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HTML text input field with currency symbol

I would like to have a text input field containing the "$" sign in the very beginning, and no matter what editing occurs to the field, for the sign to be persistent. I would be good if only numbers were accepted for input, but that's just a fancy…
User3419
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Django persistent database connection

I'm using django with apache and mod_wsgi and PostgreSQL (all on same host), and I need to handle a lot of simple dynamic page requests (hundreds per second). I faced with problem that the bottleneck is that a django don't have persistent database…
HardQuestions
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How to use a path relative to project root to H2 db-file configuration with Play Framework 2.4?

We're developing a Play 2.4 application (Java API). For dev purposes, we'd like to use a persistent H2 database with DB file path relative to the project root directory. In How to use a persistent H2 database in the Play Framework instead of…
Touko
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XCode 4.3 Unable to load persistent store UserDictionary.sqlite

I have been working on an iOS app for some time, all of a sudden I am getting the following crash every time I run the app in the iOS 5.1 Simulator. The App does not use Core Data and I am not sure what brought this about. I have deleted the app…
JonathanC
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What are the rules about concurrently accessing a persistent database

It seems the rules about concurrent access are undocumented (on the Haskell side) and simply assume the developer is familiar with the particular backend being used. For production needs this is a perfectly legitimate assumption, but for casual…
Thomas M. DuBuisson
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What are the best ways to store Graphs in persistent storage

I am wondering what the best ways to store graphs in persistent storage are, for later analysis, search, clustering, etc. I see neo4j being an option, I am curious if there are also other graph databases available. Does anyone have any insights into…
nicoslepicos
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Recommend a fast & scalable persistent Map - Java

I need a disk backed Map structure to use in a Java app. It must have the following criteria: Capable of storing millions of records (even billions) Fast lookup - the majority of operations on the Map will simply to see if a key already exists.…
Joel
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Persistent data structures in Scala

Are all immutable data structures in Scala persistent? If not, which of them are and which not? What are the behavioural characteristics of those which are persistent? Also, how do they compare to the persistent data structures in Clojure?
Abhinav Sarkar
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Android - Making Webview DomStorage persistant after app closed

I'm facing a huge problem developing an Android app which use a Webview to display datas. The website i'm using in the webview use localStorage API of HTML 5. To enable this feature i've set the webview setting like this…
jimroot25
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Detached entity passed to persist when save the child data

I'm getting this error when submitting the form: org.hibernate.PersistentObjectException: detached entity passed to persist: com.project.pmet.model.Account; nested exception is javax.persistence.PersistenceException:…
keysersoze
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What exactly does a "persistent connection" mean?

I read about "HTTP persistent connection" but somehow I don't seem to understand what does persistent mean in this context. Could you'll elaborate?
Kevin Boyd
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Persistent HttpURLConnection in Java

I am trying to write a java program that will automatically download and name some of my favorite web comics. Since I will be requesting multiple objects from the same domain, I wanted to have a persistent http connection that I could keep open…
Githaron
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Why pickle eat memory?

I trying to deal with writing huge amount of pickled data to disk by small pieces. Here is the example code: from cPickle import * from gc import collect PATH = r'd:\test.dat' @profile def func(item): for e in item: f = open(PATH, 'a',…
Gill Bates
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subset() drops attributes on vectors; how to maintain/persist them?

Let's say I have a vector where I've set a few attributes: vec <- sample(50:100,1000, replace=TRUE) attr(vec, "someattr") <- "Hello World" When I subset the vector, the attributes are dropped. For example: tmp.vec <- vec[which(vec >…
Brandon Bertelsen
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Persistent Hash Table Implementation

In a program I'm working on, I develop a large "thread tree" (at most k children per node), where each thread makes some modifications to a hash table inherited from its parent. Is there a way to implement a hash table that is somewhat "persistent"…
ManRow
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