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POHow to store data in android for a long time?
 

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  1. POHow to store data in android for a long time?
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    <p>I am trying to develop android application (first time), so I'm using SQLite to store data. But every time I run the application all data are null! I think the problem is when I run the application it recreates all the tables and they come as new empty tables!</p> <p>Can anyone help or give example how to check if the tables are already created, and if yes copy the data, if not create and that means it's a first time! How can I store data for a long time by using SQLite? If I cant what is the best way to store data?</p> <pre><code> //food private static final String food= "food"; //---- columns ----- private static final String fid = "fid"; private static final String fname= "fname"; private static final String category = "category"; private static final String quantity= "quantity"; private static final String unit= "unit"; private static final String carbs= "carbs"; //food private static final String DATABASE_CREATE_Food="CREATE TABLE " +food+" ("+fid + " INTEGER PRIMARY KEY AUTOINCREMENT , " +fname+ " TEXT NOT NULL, " +category+" TEXT Not NULL, " +quantity+" Double Not Null, " +carbs+" Integer NOT NULL, " +unit+" TEXT NOT NULL" +");"; public void onCreate(SQLiteDatabase database) { database.execSQL(DATABASE_CREATE_Food); } /** Called when the DATABASE_VERSION is changed to higher version */ @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.w(MyAppDB.class.getName(), "Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data"); db.execSQL("DROP TABLE IF EXISTS" + food); onCreate(db); } </code></pre>
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    1. COThe tables shouldn't be recreated every single time. You should post your code so a reason for the recreation can be pinpointed.
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