很多时候我们需要在项目进行中为项目添加一张表,今天终于搞清楚了。
代码如下
package com.zy.dao; import android.R.integer; import android.R.string; 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 { private static final int version = 2; private static final String DBNAME = "db_fa.db"; public DbHelper(Context context) { super(context,DBNAME,null,version); } @Override public void onCreate(sqliteDatabase db) { //创建收入表 db.execsql("create table if not exists tb_IncomeInfo (income_id integer primary key autoincrement," + "income_price varchar(10),income_date varchar(20),income_account varchar(10)," + "income_payer varchar(10),income_category varchar(10),income_remark varchar(100))"); //创建支出表 db.execsql("create table if not exists tb_ConsumeInfo (consume_id integer primary key autoincrement," + "consume_price varchar(10),consume_time varchar(20),consume_account varchar(10)," + "consume_address varchar(20),consume_category varchar(10),consume_remark varchar(100))"); } @Override public void onUpgrade(sqliteDatabase db,int oldVersion,int newVersion) { onCreate(db); } }
添加新表后要在onUpgrade执行onCreate方法,并且要把版本号更新(这个很重要!),这里我把版本号改为了。不然是无法添加进去表的!