simple sqlite example? [duplicate]

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sqlite example program in android

Hi I'm new to android and I am having some trouble finding a good tutorial for an SQLite database. What I wanted to do was to 开发者_高级运维store a line of data in the database, reference it later and then delete it once its been referenced. As I have said I am new to this sort of thing and have no clue even what any of the syntax is so if there is a simple tutorial out there I would like to know.

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try this

try { // creating a database called db and a Table inside it, called
            // userdetails. With username and password as columns.

        db = openOrCreateDatabase("UserDetails.db",
                Context.MODE_PRIVATE, null); // optional CursorFactory
        db.execSQL("drop table if exists userdetails");
        db.execSQL("create table userdetails " + " ( username TEXT,"
                + "password TEXT);");

    } catch (SQLException x) {
        x.printStackTrace();
        Log.e(LOG_TAG_NAME, "Database creation error");

    }

//.........................................................................
    // and insert values into the database table.
    try {
        db.execSQL("INSERT INTO " + "userdetails"
                + " (username,password)" + " VALUES ('hi','hello');");
        db.execSQL("INSERT INTO " + "userdetails"
                + " (username,password)" + " VALUES ('chris','gayle');");
        db.execSQL("INSERT INTO " + "userdetails"
                + " (username,password)" + " VALUES ('v','v');");
    } catch (Exception e) {
        e.printStackTrace();
        Log.e(LOG_TAG_NAME, "inserting table values error");
    }
    String[] columns = { "username", "password" };
    Cursor c = db.query("userdetails", columns, null, null, null, null,
            null);

now use the cursor to retrieve values

also have a look at

http://developer.android.com/guide/topics/data/data-storage.html#db

hope all this helps

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EZ Answer I think.

If I understand your needs I think that you will find a database is overkill. You can do this a lot easier I think with just a few lines of code. If I am correct, a "line of data" sounds like a single String that you want to persist. If that is the case SharedPreferneces is by far your best bet for easy implementation.

Check out THIS link to the Dev-Guide's Shared Preferences Data Storage section

Its as easy as initializing the Preferences, and either putting or asking for a value by key.

On the other hand if you need to store many lines of relational data, search through them, sort them, etc. then a database is what you want.

Generally, I choose the data storage mechanism based on what is being stored and how i want to retrieve it:

• Single primitives (and Strings) get stored best in SharedPreferences. This is a fast and easy implementation. You can get away with storing a couple of values if you need to to represent a more complex class. Sometimes it makes sense to create a helper class that keeps track of complex schemes.
• Serializable complex data, like parameterized Collections, that are loaded into memory all at once, long streams of text to be parsed, or if that data is a byte stream it gets stored to a file. This is not as fast and involves catching a lot of potential IO issues. But most objects are serializable or easily made that way.
• Tables of data that I want to query or provide a Cursor for because of how long they are go into a database. The start up and resource expenses of a database are huge. Writing all the helper code to use them is a pain in the extreme.

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1. Complete Step by Step SQLite Example: http://mobile.tutsplus.com/tutorials/android/android-sqlite/

2. Youtube Video Tutorial

http://www.youtube.com/watch?v=kMaBTolOuGo

1. Multiple Table Creation

http://androidforbeginners.blogspot.com/2010/01/creating-multiple-sqlite-database.html

PS: All the links are tested and working well!!

Happy Coding!!

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First place to look for tutorials should be the official Android Docs: Link.