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  • SQLite升级数据库:

    SQLiteOpenHelper子类关键代码:

    SQLite升级数据库:
    SQLiteOpenHelper子类关键代码:
    public class MyDataHelper extends SQLiteOpenHelper {
    
        Context mcontext;
        public static final String CREATE_BOOK = "create table book ("
                + "id integer primary key autoincrement, "
                + "author text, "
                + "price real, "
                + "pages integer, "
                + "name text)";
        public static final String CREATE_BOOKCAT = "create table book_cat ("
                + "id integer primary key autoincrement, "
                + "author text, "
                + "price real, "
                + "pages integer, "
                + "name text)";
    
        public MyDataHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int
                version) {
            super(context, name, factory, version);
            mcontext = context;
        }
    
        @Override
        public void onCreate(SQLiteDatabase db) {
            db.execSQL(CREATE_BOOK);
        }
    
        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            switch (oldVersion){
                case 1:
                    db.execSQL(CREATE_BOOKCAT);
                    Log.e("db", "执行创建bookcat");
                case 2:
                    db.execSQL("alter table book add column cat_id integer;");
                    Log.e("db", "执行在book表中增加列");
                default:
            }
        }
    }
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  • 原文地址:https://www.cnblogs.com/itfenqing/p/6742885.html
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