Android中安装轻量级数据库SQLite,现在测试数据库基本操作。
数据库基本操作:创建表,插入,删除可以用execSQL();读取可以用rawQuery();这两个函数都可以标准SQL语句进行操作.
- package com.test.sql;
- import android.app.Activity;
- import android.content.Context;
- import android.database.Cursor;
- import android.database.sqlite.SQLiteDatabase;
- import android.database.sqlite.SQLiteOpenHelper;
- import android.os.Bundle;
- import android.util.Log;
- public class test_sql extends Activity
- {
- DatabaseHelper mOpenHelper;
- private static final String DATABASE_NAME = "test.db";
- private static final int DATABASE_VERSION = 1;
- private static class DatabaseHelper extends SQLiteOpenHelper {
- DatabaseHelper(Context context) {
- super(context, DATABASE_NAME, null, DATABASE_VERSION);
- }
- @Override
- public void onCreate(SQLiteDatabase db)
- {
- //新建一个用户表
- //共有5项:Id Pwd Name OnLineTime Level
- db.execSQL("CREATE TABLE User_Table ('Id' INT,'Pwd' VARCHAR,'Name' VARCHAR,'OnLineTime' INT,'Level' INT)");
- }
- @Override
- public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
- }
- }
- /** Called when the activity is first created. */
- @Override
- public void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
- setContentView(R.layout.main);
- mOpenHelper = new DatabaseHelper(this);
- SQLiteDatabase db = mOpenHelper.getWritableDatabase();
- //清空数据
- db.execSQL("DELETE FROM User_Table");
- //插入数据10000 123456 "jdh" 0 0
- //插入数据10001 123456 "jim" 0 0
- db.execSQL("INSERT INTO User_Table VALUES (?,?,?,?,?)", new Object[]{10000,"123456","jdh",0,0});
- db.execSQL("INSERT INTO User_Table VALUES (?,?,?,?,?)", new Object[]{10001,"123456","jim",0,0});
- //读取数据
- Cursor cursor = db.rawQuery("SELECT * FROM User_Table WHERE Name = ?",new String[]{"jdh"});
- while (cursor.moveToNext())
- {
- String str = cursor.getInt(0) + cursor.getString(1) + cursor.getString(2) + cursor.getInt(3) + cursor.getInt(4);
- Log.i("str:", str);
- }
- }
- }
原文链接:http://blog.csdn.net/jdh99/article/details/6709477
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