import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
SQLiteDatabase db = openOrCreateDatabase("stu.db", MODE_PRIVATE, null);
// 即只能存储int类型,写成integer比int更好;autoincrement即组件自增
db.execSQL("create table if not exits stutb(_id integer private key autoincrement,name text not null,sex text not null, age text not null)");
/*
* table指表的名字
* nullColumnHack为默认值,null
* values是contentvalue,类似于HashMap
*/
ContentValues values=new ContentValues();
values.put("name","张三");
values.put("sex", "男");
values.put("age", 19);
//db.insert("stutb", null, values)返回long值,可以赋值,有用再用,没用也没事
long rowId= db.insert("stutb", null, values);
values.clear();
values.put("name","张三丰");
values.put("sex", "男");
values.put("age", 99);
db.insert("stutb", null, values);
values.clear();
values.put("name","张三疯");
values.put("sex", "男");
values.put("age", 59);
db.insert("stutb", null, values);
values.clear();
values.put("name","张四");
values.put("sex", "男");
values.put("age", 29);
db.insert("stutb", null, values);
values.clear();
values.put("name","张五");
values.put("sex", "男");
values.put("age", 59);
db.insert("stutb", null, values);
values.clear();
values.put("sex", "女");
//查询条件
db.update("stutb", values, "_id>?", new String[]{"3"});//将id大于三的性别全部改成女
db.delete("stutb", "name like?", new String[]{"%丰%"});//删除所有名字中带有丰的人
Cursor c= db.query("studb", null, "_id>?", new String[]{"0"}, null, null, "name");//查询
if (c!=null) {
String[] columns= c.getColumnNames();
while (c.moveToNext()) {
for (String columnName:columns) {
Log.d("Main", c.getString(c.getColumnIndex(columnName)));
}
}c.close();//while之外,进行游标的关闭
}db.close();//if之外,进行db的关闭
}
}
Shirey
星箜下