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NotesDbAdapter example is for one table, how about multiple tables?

Tags:

android

sqlite

I've checked the NotesDbAdapter example, and I noticed that is for a single table only. (notes)

1) I am wondering how would this be done for multiple tables? For example I have 3 tables for now. How would I handle all the upgrade, fetch, delete from these three tables?

2) I see defined properties for the table columns

public static final String KEY_TITLE = "title";
public static final String KEY_BODY = "body";
public static final String KEY_ROWID = "_id";

How would you define the columns for a multiple table situation?

like image 237
Pentium10 Avatar asked Feb 26 '10 06:02

Pentium10


1 Answers

For my application I created a class to define the database :

public final class MyApplicationDb
{
    public static String DATABASE_NAME = "my_application_db";
    public static int DATABASE_VERSION = 1;

    public static final class Table1
    {
        public static String TABLE_NAME = "table1";
        public static String ID = "_id";
        public static String DAY = "day";
        public static String NAME = "name";
        public static String SOURCE = "source";
        public static String[] COLUMNS = { ID, DAY, NAME, SOURCE };
    }
    public static final class Table2
    {
        public static String TABLE_NAME = "table2";
        public static String ID = "_id";
        public static String CONTACT_ID = "contactId";
        public static String CONTACT_NAME = "contactName";
        public static String LAST_WISH_DATE = "lastWishDate";
        public static String[] COLUMNS = { ID, CONTACT_ID, CONTACT_NAME, LAST_WISH_DATE };
    }
}

And 2 sql scripts for creating and updating the db res/raw/db_create.sql and res/raw/db_update.sql

/* db_create.sql */
create table table1(
  _id integer primary key autoincrement,
  day char(5) not null,
  name varchar(64) not null,
  source varchar(64) not null);
create table table2(
  _id integer primary key autoincrement,
  contactId integer not null,
  contactName text not null,
  lastWishDate char(10) null);


/* db_update.sql */
DROP TABLE IF EXISTS table1;
DROP TABLE IF EXISTS table2

And Another class for creating/updating/accessing the database which is similar to NotesDbAdapter except it uses the sql script to create/update the database instead of constants. (look here to see how to do that)

like image 194
2 revs Avatar answered Oct 17 '22 21:10

2 revs