这期内容当中小编将会给大家带来有关使用SQL语句怎么实现模糊查询，文章内容丰富且以专业的角度为大家分析和叙述，阅读完这篇文章希望大家可以有所收获。
在main.xml中：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/mylayout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:gravity="center_horizontal">
<Button
android:id="@+id/findBut"
android:layout_marginTop="8dp"
android:background="#0066ff"
android:textColor="#ffffff"
android:layout_width="100dp"
android:layout_height="40dp"
android:text="查询全部数据" />
</LinearLayout>
在MyDatabaseHelper.java类中：
package com.li.sqlite;
//数据库的辅助操作类
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class MyDatabaseHelper extends SQLiteOpenHelper {
private static final String DATABASENAME = "liyewen.db" ;
private static final int DATABASERVERSION = 1 ; // 设置数据库的版本
private static final String TABLENAME = "mytab" ;
public MyDatabaseHelper(Context context) { // 用户最关心的也肯定只是Context
super(context, DATABASENAME, null, DATABASERVERSION);
}
@Override
public void onCreate(SQLiteDatabase db) { // 创建数据表
String sql = "CREATE TABLE " + TABLENAME + "("
+ "id INTEGER PRIMARY KEY ," // 在SQLite中设置为Integer、PRIMARY KEY则ID自动增长
+ "name VARCHAR(50) NOT NULL ,"
+ "birthday DATE NOT NULL" + ")";
db.execSQL(sql) ; // 执行SQL
System.out.println("****************** 创建：onCreate()。");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
String sql = "DROP TABLE IF EXISTS " + TABLENAME ;
db.execSQL(sql) ;
System.out.println("****************** 更新：onUpgrade()。");
this.onCreate(db) ;
}
}
在MytabCursor.java类中：
package com.li.sqlite;
import java.util.ArrayList;
import java.util.List;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
public class MytabCursor {
private static final String TABLENAME = "mytab" ;
private SQLiteDatabase db = null ;
public MytabCursor(SQLiteDatabase db) {
this.db = db ;
}
public List<String> find(){
List<String> all = new ArrayList<String>() ; // 此时只是String
String sql = "SELECT id,name,birthday FROM " + TABLENAME + " WHERE name LIKE ? OR birthday LIKE ?" ;
String keyWord = "2" ; // 查询关键字 ，应该由方法定义
String args[] = new String[] { "%" + keyWord + "%", "%" + keyWord + "%" };
Cursor result = this.db.rawQuery(sql, args); // 执行查询语句
for (result.moveToFirst(); !result.isAfterLast(); result.moveToNext()) { // 采用循环的方式检索数据
all.add("【" + result.getInt(0) + "】" + " " + result.getString(1)
+ "，" + result.getString(2));
}
this.db.close() ;
return all ;
}
}
在MySQLiteDemo.java中：
package com.li.sqlite;
import android.app.Activity;
import android.database.sqlite.SQLiteOpenHelper;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.ListView;
public class MySQLiteDemo extends Activity {
private Button findBut = null;
private SQLiteOpenHelper helper = null;
private LinearLayout mylayout = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
super.setContentView(R.layout.main);
this.findBut = (Button)super.findViewById(R.id.findBut);
this.mylayout = (LinearLayout)super.findViewById(R.id.mylayout);
this.findBut.setOnClickListener(new OnClickListenerImpl());
}
private class OnClickListenerImpl implements OnClickListener{
public void onClick(View v) {
MySQLiteDemo.this.helper = new MyDatabaseHelper(MySQLiteDemo.this);
ListView listView = new ListView(MySQLiteDemo.this);
listView.setAdapter( //设置数据
new ArrayAdapter<String> //所有的数据是字符串
(MySQLiteDemo.this, //上下文
android.R.layout.simple_list_item_1, //列表显示的布局
new MytabCursor( //实例化查询
MySQLiteDemo.this.helper.getReadableDatabase()) //取得SQLiteDatabase对象
.find())); //调用find()方法，返回List<String>
MySQLiteDemo.this.mylayout.addView(listView);
}
}
}
上述就是小编为大家分享的使用SQL语句怎么实现模糊查询了，如果刚好有类似的疑惑，不妨参照上述分析进行理解。如果想知道更多相关知识，欢迎关注亿速云行业资讯频道。
