Android SQLite Database Upgrade

Scene:

Database Version V1 has a persion table

Database version v2 new table student

Database version v3 persion table A new field

1  PackageCom.example.natedb;2 3 ImportAndroid.content.Context;4 Importandroid.database.SQLException;5 Importandroid.database.sqlite.SQLiteDatabase;6 Importandroid.database.sqlite.SQLiteDatabase.CursorFactory;7 ImportAndroid.database.sqlite.SQLiteOpenHelper;8 9  Public classSqlDbextendsSqliteopenhelper {Ten  One     Private Final Static intVersion = 3; A      PublicSqlDb (Context context) { -          This(Context, "lihao.db",NULL, version); -     } the      PublicSqlDb (Context context, String name, Cursorfactory factory, -             intversion) { -         Super(context, name, Factory, version); -          +     } -  + @Override A      Public voidonCreate (Sqlitedatabase db) { at         //TODO auto-generated Method Stub -     //db.execsql ("CREATE TABLE person (_id integer PRIMARY key autoincrement,name text,age text)"); -         //Latest -Db.execsql ("CREATE TABLE person (_id integer primary key autoincrement,name text,age Text,score txt)"); -Db.execsql ("CREATE TABLE student (_id integer PRIMARY key autoincrement,name text,age text)"); -     } in  - @Override to      Public voidOnupgrade (Sqlitedatabase db,intOldversion,intnewversion) { +         //TODO auto-generated Method Stub -         intCurrentVersion =oldversion; the db.begintransaction (); *         Try { $             if(CurrentVersion = = 1) {Panax NotoginsengDb.execsql ("CREATE TABLE student (_id integer PRIMARY key autoincrement,name text,age text)"); -CurrentVersion = 2; the             } +  A             if(CurrentVersion = = 2) { theString temptable = "Person_temp"; +                 //Modify the original table as a temporary table -Db.execsql ("ALTER TABLE person rename to" +temptable); $                  $                 //Create a new table -Db.execsql ("CREATE TABLE person (_id integer primary key autoincrement,name text,age Text,score txt)"); -                  the                 //Copying Data -Db.execsql ("INSERT into person (name,age) Select Name,age from" +temptable);Wuyi                  the                 //Delete temporary table -Db.execsql ("drop table" +temptable); Wu             } - db.settransactionsuccessful (); About}Catch(SQLException e) { $             //TODO auto-generated Catch block - e.printstacktrace (); -}finally{ - db.endtransaction (); A         } +          the          -     } $  the      the}

Android SQLite Database upgrade