android sqlite3查询

package com.eoeAndroid.SQLite;import android.app.Activity;import android.content.Context;import android.database.Cursor;import android.database.SQLException;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;import android.os.Bundle;import android.util.Log;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;public class ActivityMain extends Activity {OnClickListener listener1 = null;OnClickListener listener2 = null;OnClickListener listener3 = null;OnClickListener listener4 = null;OnClickListener listener5 = null;Button button1;Button button2;Button button3;Button button4;Button button5;DatabaseHelper mOpenHelper;private static final String DATABASE_NAME = "dbForTest.db";private static final int DATABASE_VERSION = 1;private static final String TABLE_NAME = "diary";private static final String TITLE = "title";private static final String BODY = "body";private static class DatabaseHelper extends SQLiteOpenHelper {DatabaseHelper(Context context) {super(context, DATABASE_NAME, null, DATABASE_VERSION);}@Overridepublic void onCreate(SQLiteDatabase db) {String sql = "CREATE TABLE " + TABLE_NAME + " (" + TITLE+ " text not null, " + BODY + " text not null " + ");";Log.i("haiyang:createDB=", sql);Log.v("lunzi", sql);db.execSQL(sql);}@Overridepublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {}}@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);prepareListener();initLayout();mOpenHelper = new DatabaseHelper(this);}private void initLayout() {button1 = (Button) findViewById(R.id.button1);button1.setOnClickListener(listener1);button2 = (Button) findViewById(R.id.button2);button2.setOnClickListener(listener2);button3 = (Button) findViewById(R.id.button3);button3.setOnClickListener(listener3);button4 = (Button) findViewById(R.id.button4);button4.setOnClickListener(listener4);button5 = (Button) findViewById(R.id.button5);button5.setOnClickListener(listener5);}private void prepareListener() {listener1 = new OnClickListener() {public void onClick(View v) {CreateTable();}};listener2 = new OnClickListener() {public void onClick(View v) {dropTable();}};listener3 = new OnClickListener() {public void onClick(View v) {insertItem();}};listener4 = new OnClickListener() {public void onClick(View v) {deleteItem();}};listener5 = new OnClickListener() {public void onClick(View v) {showItems();}};}/* * 重新建立数据表 */private void CreateTable() {SQLiteDatabase db = mOpenHelper.getWritableDatabase();String sql = "CREATE TABLE " + TABLE_NAME + " (" + TITLE+ " text not null, " + BODY + " text not null " + ");";Log.i("haiyang:createDB=", sql);Log.v("lunzi", sql);try {db.execSQL("DROP TABLE IF EXISTS diary");db.execSQL(sql);setTitle("数据表成功重建");} catch (SQLException e) {setTitle("数据表重建错误");}}/* * 删除数据表 */private void dropTable() {SQLiteDatabase db = mOpenHelper.getWritableDatabase();String sql = "drop table " + TABLE_NAME;Log.v("lunzi", sql);try {db.execSQL(sql);setTitle("数据表成功删除：" + sql);} catch (SQLException e) {setTitle("数据表删除错误");}}/* * 插入两条数据 */private void insertItem() {SQLiteDatabase db = mOpenHelper.getWritableDatabase();String sql1 = "insert into " + TABLE_NAME + " (" + TITLE + ", " + BODY+ ") values('haiyang', 'android的发展真是迅速啊');";String sql2 = "insert into " + TABLE_NAME + " (" + TITLE + ", " + BODY+ ") values('icesky', 'android的发展真是迅速啊');";try {Log.i("haiyang:sql1=", sql1);Log.v("lunzi", sql1);Log.i("haiyang:sql2=", sql2);Log.v("lunzi", sql2);db.execSQL(sql1);db.execSQL(sql2);setTitle("插入两条数据成功");} catch (SQLException e) {setTitle("插入两条数据失败");}}/* * 删除其中的一条数据 */private void deleteItem() {try {SQLiteDatabase db = mOpenHelper.getWritableDatabase();db.delete(TABLE_NAME, " title = 'haiyang'", null);setTitle("删除title为haiyang的一条记录");} catch (SQLException e) {}}/* * 在屏幕的title区域显示当前数据表当中的数据的条数。 */private void showItems() {SQLiteDatabase db = mOpenHelper.getReadableDatabase();String col[] = { TITLE, BODY };Cursor cur = db.query(TABLE_NAME, col, null, null, null, null, null);Integer num = cur.getCount();cur.moveToFirst();while (!cur.isAfterLast()) {Log.v("lunzi", "cols:"+cur.getString(0)+"-"+cur.getString(1));System.out.println("cols:"+cur.getString(0)+"-"+cur.getString(1));cur.moveToNext();}    db.close();/*for (int i=0;i<num;i++) {Log.v("lunzi", cur.getString(i));}*/setTitle(Integer.toString(num) + " 条记录");}}
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