<p>sqlite是一种小型的数据库,他的特点就是体积小,不依赖于第三方软件,在使用的时候只需要提取其中的文件就可以了,因为一个表格对应一个.db文件,所以在某些应用,比如android设备,ios设备上都能很方便使用。</p><p> </p><p>在android中,使用android资料库自带的sqlIte包可以创建数据库</p>
import android.content.ContentValues; import android.content.Context; import android.database.sqlite.sqliteDatabase; import android.database.sqlite.sqliteDatabase.CursorFactory; import android.database.sqlite.sqliteOpenHelper; public class DBhelper extends sqliteOpenHelper { public static final String TB_NAME = "people"; public static final String ID = "_id"; public static final String username = "username"; public static final String password = "password"; public DBhelper(Context context,String name,CursorFactory factory,int version) { super(context,name,factory,version); this.getWritableDatabase(); } /** * should be invoke when you never use DBhelper * To release the database and etc. */ public void Close() { this.getWritableDatabase().close(); } public void onCreate(sqliteDatabase db) { db.execsql("CREATE TABLE IF NOT EXISTS " + TB_NAME + " (" + ID + " INTEGER PRIMARY KEY," + username + " VARCHAR," + password + " VARCHAR)"); } public void onUpgrade(sqliteDatabase db,int oldVersion,int newVersion) { db.execsql("DROP TABLE IF EXISTS "+TB_NAME); onCreate(db); }
非常的方便,取用数据时候,比如在activity中,使用
sqliteDatabase sdb = dbHelper.getWritableDatabase(); String sql="select * from people where username=? and password=?"; Cursor cursor= sdb.rawQuery(sql,new String[]{username,password});
这里配合cursor读取数据库表格中的数据就可以了。游标的特定也是比较有意思~