安卓sqlite 數據庫 學習筆記

1.建立一個數據庫

package com.sqlite.db;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;

public class Persondb extends SQLiteOpenHelper {

	public Persondb(Context context) {
	    super(context, "person.db", null, 2);
	}

	@Override
	public void onCreate(SQLiteDatabase db) {
		db.execSQL(
				"create table person (id integer primary key autoincrement,"
				+ "name varchar(20),number varchar(20))"
			);
	}

	@Override
	public void onUpgrade(SQLiteDatabase db, int arg1, int arg2) {
		db.execSQL("ALTER table person add account varchar(20)");
	}

}

2.建立一個數據庫操做類

package com.sqlite.person.dao;

import java.util.ArrayList;
import java.util.List;

import com.sqlite.db.Persondb;
import com.sqlite.person.domain.Person;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class PersonDao {
	private SQLiteOpenHelper helper;
	public PersonDao(Context context){
		helper = new Persondb(context);
	}
	
	/**
	 * 添加一條數據
	 * @param name
	 * @param number
	 */
	public void add(String name, String number)
	{
		SQLiteDatabase db = helper.getWritableDatabase();
		/*
		db.execSQL(
			"INSERT INTO person (name,number)VALUES(?,?)",
			new Object[]{name, number}
		);*/
		ContentValues values = new ContentValues();
		values.put("name", name);
		values.put("number", number);
		db.insert("person", null, values);
		db.close();
	}
	
	/**
	 * 測試查找數據庫是否有這條記錄
	 * @param name
	 * @return
	 */
	public boolean find(String name)
	{
		SQLiteDatabase db = helper.getReadableDatabase();
		/*
		Cursor cursor = db.rawQuery(
			"SELECT * FROM person WHERE name = ?",
			new String[]{name}
		);*/
		Cursor cursor = db.query("person", null, "name=?", new String[]{name}, null, null, null);
		boolean res = cursor.moveToNext();
		cursor.close();
		db.close();
		return res;
	}
	
	/**
	 * 修改數據
	 * @param name
	 * @param number
	 */
	public void update(String name, String number)
	{
		SQLiteDatabase db = helper.getWritableDatabase();
		/*
		db.execSQL(
			"UPDATE person SET number = ? WHERE name = ?", 
			new Object[]{number,name}
		);*/
		ContentValues values = new ContentValues();
		values.put("number", number);
		db.update("person", values, "name=?", new String[]{name});
		db.close();
	}
	
	/**
	 * 刪除
	 * @param name
	 */
	public void del(String name)
	{
		SQLiteDatabase db = helper.getWritableDatabase();
		/*
		db.execSQL(
			"DELETE FROM person WHERE name = ?", 
			new Object[]{name}
		);*/
		db.delete("person", "name=?", new String[]{name});
		db.close();
	}
	
	/**
	 * 返回全部記錄
	 * @return
	 */
	public List<Person> findAll()
	{
		SQLiteDatabase db = helper.getReadableDatabase();
		//Cursor cursor = db.rawQuery("SELECT * FROM person", null);
		Cursor cursor = db.query("person", new String[]{"name","id","number"}, null, null, null, null,null);
		List<Person> persons = new ArrayList<Person>();
		while(cursor.moveToNext()){
			Person p = new Person();
			p.setId(cursor.getInt(cursor.getColumnIndex("id")));
			p.setName(cursor.getString(cursor.getColumnIndex("name")));
			p.setNumber(cursor.getString(cursor.getColumnIndex("number")));
			persons.add(p);
		}
		cursor.close();
		db.close();
		return persons;
	}
	String s;
	public void transaction(String name1,String name2,int account)
	{
		SQLiteDatabase db = helper.getWritableDatabase();
		db.beginTransaction();
		try {
			ContentValues val1 = new ContentValues(); 
			ContentValues val2 = new ContentValues(); 
			val1.put("account", account);
			val2.put("account", account);
			db.update("person", val1, "name=?", new String[]{name1});
			db.update("person", val2, "name=?", new String[]{name2});
			s.equals("xx");
			db.setTransactionSuccessful();
		} catch (Exception e) {
			// TODO: handle exception
		} finally {
			db.endTransaction();
			db.close();
		}
	}
}

3.建立一個實體類domain

package com.sqlite.person.domain;

public class Person {
	private String name;
	private String number;
	private int id;
	public Person() {
	}
	public Person(String name, String number) {
		this.name = name;
		this.number = number;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getNumber() {
		return number;
	}
	public void setNumber(String number) {
		this.number = number;
	}
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String toString() {
		return "Person [name=" + name + ", number=" + number + ", id=" + id
				+ "]";
	}
	
	
}

4.建立一個測試類

package com.sqlite.test;

import java.util.List;

import com.sqlite.db.Persondb;
import com.sqlite.person.dao.PersonDao;
import com.sqlite.person.domain.Person;

import android.content.ContentValues;
import android.database.sqlite.SQLiteDatabase;
import android.test.AndroidTestCase;

public class DbTest extends AndroidTestCase {
	
	public void testCreate()
	{
		Persondb pdb = new Persondb(getContext());
		pdb.getWritableDatabase();
	}
	
	/**
	 * 添加
	 */
	public void testAdd()
	{
		PersonDao pd = new PersonDao(getContext());
		pd.add("xiaohei", "133000");
	}
	
	/*
	 * 測試查詢
	 **/
	public void testFind()
	{
		PersonDao pd = new PersonDao(getContext());
		boolean res = pd.find("testTang");
		assertEquals(true, res);
	}
	
	/**
	 * 測試修改
	 */
	public void testUpdate()
	{
		PersonDao pd = new PersonDao(getContext());
		pd.update("testTang", "150000");
	}
	
	/**
	 * 測試刪除
	 */
	public void testDel()
	{
		PersonDao pd = new PersonDao(getContext());
		pd.del("testTang");
	}

	/**
	 * 測試查詢全部
	 */
	public void testFindAll()
	{
		PersonDao pd = new PersonDao(getContext());
		List<Person> list = pd.findAll();
		StringBuffer bf = new StringBuffer();
		for (Person p : list) {
			bf.append(p.toString());
		}
		System.out.println(bf);
	}
	
	public void testTransaction()
	{
		PersonDao pd = new PersonDao(getContext());
		pd.transaction("testTang", "xiaohei", 1000);
	}
}

注意測試類必須加清單文件中加入一些代碼纔有效()

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.sqlite.db"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="19"
        android:targetSdkVersion="19" />
    <instrumentation #這裏測試必須加
        android:name="android.test.InstrumentationTestRunner"
        android:targetPackage="com.sqlite.db" />
    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.sqlite.db.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <uses-library android:name="android.test.runner" />#還有這裏測試也得加
    </application>

</manifest>