SQLite数据库存储

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sqlite数据库存储

方法一、命令行模式。在环境变量Path中配置Platform-tools的路径,输入 adb shell,输入 cd /data/data/cn.bzu.tong.sqlite/databases,输入 sqlite3 BookStore.db,输入 .table查看数据库中的表,输入.scheme,查看建表语句,输入 select * from Book查看表中内容(自己运行显示不出内容)。

方法二、Navicat模式。模拟器运行,点击Create database等按钮,每一次都将模拟器中的BookStore.db导出,在Navicat中新建连接后导入该数据库,打开book表查看表中信息。



一、运行效果

1、Create databases

2、Add data 添加数据

3、Update data 更新数据

4、Delete Data 删除数据

5、Quary data 查询数据

Logcat显示如下图:

7、模拟器界面MainActivity.xml

二、核心代码

MainActivity.java

package cn.bzu.tong.sqlite;

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.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import cn.bzu.tong.sqlist.R;
import cn.bzu.tong.sqlite.db.DBHelper;

public class MainActivity extends Activity {

	private DBHelper dbHelper;
	private Button createDatabase,addData,updateData,deleteData,queryData;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        dbHelper = new DBHelper(this,"BookStore.db",null,2);
        queryData = (Button) findViewById(R.id.query_data);
        deleteData = (Button) findViewById(R.id.delete_data);
        updateData = (Button) findViewById(R.id.update_data);
        addData = (Button) findViewById(R.id.add_data);
        createDatabase = (Button) findViewById(R.id.creat_database);
        createDatabase.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View view) {

				dbHelper.getWritableDatabase();
			}
		});
        addData.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View view) {

				sqliteDatabase db = dbHelper.getWritableDatabase();
				ContentValues values = new ContentValues();
				//开始组装第一条数据
				values.put("name","The Da Vinci Code");
				values.put("author","Dan Brown");
				values.put("pages",454);
				values.put("price",16.96);
				db.insert("Book",values);//插入第一条数据
				values.clear();
				//开始组装第二条数据
				
				
				}
		});
        updateData.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View view) {

				sqliteDatabase db = dbHelper.getWritableDatabase();
				ContentValues values = new ContentValues();
				values.put("price",10.99);
				db.update("Book",values,"name=?",new String[]{"The Da Vinci Code"});
			}
		});
        deleteData.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View view) {

				sqliteDatabase db = dbHelper.getWritableDatabase();
				db.delete("Book","pages > ?",new String[]{"400"});//范围
			}
		 queryData.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View view) {

				sqliteDatabase db = dbHelper.getWritableDatabase();
				//查询Book表中所有数据
				Cursor cursor = db.query("Book",null);
				if(cursor.moveToFirst()){
					do{
						//遍历Cursor对象,取出数据并打印
						String name = cursor.getString(cursor.getColumnIndex("name"));
						String author = cursor.getString(cursor.getColumnIndex("author"));
						int pages = cursor.getInt(cursor.getColumnIndex("pages"));
						double price = cursor.getDouble(cursor.getColumnIndex("price"));
						Log.d("MainActivity","book name is "+name);
						
						
						
						
					}while(cursor.moveToNext());
				}
				cursor.close();
			}
		});
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main,menu);
        return true;
    }
    
} 

DBHelper.java

package cn.bzu.tong.sqlite.db;

import android.content.Context;
import android.database.sqlite.sqliteDatabase;
import android.database.sqlite.sqliteDatabase.CursorFactory;
import android.database.sqlite.sqliteOpenHelper;
import android.widget.Toast;

public class DBHelper extends sqliteOpenHelper {

	public static final String CREATE_TABLE_BOOK = "create table book("
			+ "id integer primary key autoincrement," + "author text,"
			+ "price real," + "pages integer," + "name text)";
	private Context mContext;

	public static final String CREATE_TABLE_CATEGORY="create table Category(id integer primary key autoincrement," +
			"category_name text,category_code integer)";
	public DBHelper(Context context,String name,CursorFactory factory,int version) {
		super(context,name,factory,version);
		mContext = context;
	}

	@Override
	public void onCreate(sqliteDatabase db) {

		db.execsql(CREATE_TABLE_BOOK);
		db.execsql(CREATE_TABLE_CATEGORY);
		Toast.makeText(mContext,"create succeeded",Toast.LENGTH_SHORT).show();
	}

	@Override
	public void onUpgrade(sqliteDatabase db,int oldVersion,int newVersion) {

		db.execsql("drop table if exists Book");
		db.execsql("drop table if exists Category");
		onCreate(db);
	}

}

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:orientation="vertical" >

    <Button
        android:id="@+id/creat_database"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Create database" />
    <Button 
        android:id="@+id/add_data"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Add Data"/>
    <Button 
        android:id="@+id/update_data"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Update Data"/>
    <Button 
        android:id="@+id/delete_data"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Delete Data"/>
    <Button 
        android:id="@+id/query_data"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Query Data"/>
    

</LinearLayout>
原文链接:https://www.f2er.com/sqlite/198653.html

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