Android的SQLite基本操作
浏览数：19 /
时间：2015年06月11日
涉及SQLite的增删改查，结果用log显示
package com.example.sqlconnecttest;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBHelper extends SQLiteOpenHelper{
/*
* 必须有的构造器
*/
public DBHelper(Context context, String name, CursorFactory factory,
int version) {
super(context, name, factory, version);
}
/*
* 当第一次创建数据库时，就调用该方法
*/
@Override
public void onCreate(SQLiteDatabase db) {
Log.i("createDatabases", "创建数据库--->");
}
/*
* 当更新数据库时，调用该方法
*/
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.i("updateDatabase", "更新数据库--->");
}
}
package com.example.sqlconnecttest;
import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity implements OnClickListener{
private Button createDatabase;
private Button createTable;
private Button insert;
private Button select;
private Button update;
private Button delete;
private final String DATABASE_NAME = "myDatabase";
private SQLiteDatabase mySQLiteDatabase = null;
private final String TABLE_NAME = "user";
private String SQL =
"CREATE TABLE [user] ("+
"[id] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, "+
"[username] VARCHAR NOT NULL, "+
"[password] VARCHAR NOT NULL, "+
"[phoneNumber] VARCHAR NOT NULL)";
private DBHelper db;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
createView();
setListener();
}
private void createView(){
createDatabase = (Button) findViewById(R.id.createDatabase);
createTable = (Button) findViewById(R.id.createTable);
insert = (Button) findViewById(R.id.insert);
select = (Button) findViewById(R.id.select);
update = (Button) findViewById(R.id.update);
delete = (Button) findViewById(R.id.delete);
}
//加监听器
private void setListener(){
createDatabase.setOnClickListener(this);
createTable.setOnClickListener(this);
insert.setOnClickListener(this);
select.setOnClickListener(this);
update.setOnClickListener(this);
delete.setOnClickListener(this);
}
//各种监听方法
@Override
public void onClick(View view) {
switch(view.getId()){
case R.id.createDatabase:
{
db = new DBHelper(MainActivity.this,DATABASE_NAME,null,1);
mySQLiteDatabase = db.getWritableDatabase();
Log.i("数据库对象", mySQLiteDatabase.toString());
//System.out.print("数据库对象"+mySQLiteDatabase);
break;
}
case R.id.createTable:
{
db = new DBHelper(MainActivity.this, DATABASE_NAME, null, 1);
mySQLiteDatabase = db.getWritableDatabase();
try {
mySQLiteDatabase.execSQL(SQL);
Log.i("创建表", SQL);
} catch (SQLException e) {
e.printStackTrace();
Log.i("创建表--》", "创建表失败----------------》");
}
break;
}
case R.id.insert:
{
db = new DBHelper(MainActivity.this, DATABASE_NAME, null, 1);
mySQLiteDatabase = db.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put("username", "老爸");
cv.put("password", 123456);
cv.put("phoneNumber", "134756658888");
long n = mySQLiteDatabase.insert(TABLE_NAME, null, cv);
Log.i("插入数据", n + "");
mySQLiteDatabase.close();
break;
}
case R.id.select:
{
db = new DBHelper(MainActivity.this, DATABASE_NAME, null, 1);
mySQLiteDatabase = db.getReadableDatabase();
/**
* 参数1：表名
* 参数2：要显示的列
* 参数3：where语句
* 参数4：where语句的条件值
* 参数5：分组方式
* 参数6：having条件
* 参数7：排序方式
*/
Cursor cursor = mySQLiteDatabase.query(TABLE_NAME,
new String[]{"id","username","password","phoneNumber"},
null, null, null, null, null);
while(cursor.moveToNext()){
int id = cursor.getInt(cursor.getColumnIndex("id"));
String username = cursor.getString(cursor.getColumnIndex("username"));
String password = cursor.getString(cursor.getColumnIndex("password"));
String phoneNumber = cursor.getString(cursor.getColumnIndex("phoneNumber"));
Log.i("query-->", "id:" + id + "userName:" + username +
"password" + password + "phoneNumber" + phoneNumber);
}
mySQLiteDatabase.close();
break;
}
case R.id.update:
{
db = new DBHelper(MainActivity.this, DATABASE_NAME, null, 1);
mySQLiteDatabase = db.getWritableDatabase();
ContentValues cv1 = new ContentValues();
cv1.put("username", "admin");
cv1.put("password", "admin");
cv1.put("phoneNumber", "1388888");
String whereClause = "id" + "=?";
String[] whereArgs = {"8"};
/*
* 参数1：表名
* 参数2：是一个ContextValue对象，就是更新的值
* 参数3：where语句条件
* 参数4：where条件的值
*/
int index = mySQLiteDatabase.update(TABLE_NAME, cv1, whereClause, whereArgs);
Log.i("update-->", index + "");
break;
}
case R.id.delete:
{
db = new DBHelper(MainActivity.this, DATABASE_NAME, null, 1);
mySQLiteDatabase = db.getWritableDatabase();
/***
* 参数1：表名
* 参数2：where语句字段
* 参数3：where语句字段的值
*/
String whereClause1 = "id" + "=?";
String[] whereArgs1 = {"1"};
int num = mySQLiteDatabase.delete(TABLE_NAME, whereClause1, whereArgs1);
Log.i("删除记录-->", num + "");
mySQLiteDatabase.close();
break;
}
default:
break;
}
}
}
<RelativeLayout 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"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.sqlconnecttest.MainActivity" >
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="SQLite数据库"
/>
<Button
android:id="@+id/createDatabase"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/textView"
android:text="创建一个数据库"
/>
<Button
android:id="@+id/createTable"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/createDatabase"
android:text="创建一张表"
/>
<Button
android:id="@+id/insert"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/createTable"
android:text="插入数据"
/>
<Button
android:id="@+id/select"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/insert"
android:text="查询数据"
/>
<Button
android:id="@+id/update"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/select"
android:text="更新数据"
/>
<Button
android:id="@+id/delete"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/update"
android:text="删除数据"
/>
</RelativeLayout>
运行结果
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