android sqlite使用之模糊查询数据库数据的三种方式

android应用开发中常常需要记录一下数据,而在查询的时候如何实现模糊查询呢?很少有文章来做这样的介绍,所以这里简单的介绍下三种sqlite的模糊查询方式,直接上代码把:



package com.example.utils;
 
import java.util.ArrayList;
 
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
 
public class DBManage extends SQLiteOpenHelper {
 
    static int init_version = 1;
    static String database_name = "android_sqlite_test.db";
    static String tab_name = "uer_log";
    static String tab_field01 = "_id";
    static String tab_field02 = "log_name";
    SQLiteDatabase mDatabase;
 
    public DBManage(Context context) {
        super(context, database_name, null, init_version);
        // TODO Auto-generated constructor stub
        mDatabase = getWritableDatabase();
    }
 
    @Override
    public void onCreate(SQLiteDatabase db) {
        // TODO Auto-generated method stub
        String sql = "create table " + tab_name + " ( " + tab_field01
                + " integer primary key , " + tab_field02 + " text  not null) ";
 
        db.execSQL(sql);
    }
 
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // TODO Auto-generated method stub
 
    }
 
    /**
     * 插入记录
     *
     * @param u
     * @return
     */
    public boolean insertData(String... str) {
 
        int request_int = 0;
        for (int i = 0; i < str.length; i++) {
 
            // 实例化一个ContentValues 对象 ,作用,收集数据,方便于SQLite执行增,删,改,查
            ContentValues contentValues = new ContentValues();
            contentValues.put(tab_field02, str[i]);
            mDatabase.insert(tab_name, null, contentValues);
            request_int++;
        }
        return str.length == request_int;
    }
 
    // 根据条件模糊查询数据库数据
    public ArrayList<String> query(int top_int, String... str) {
        ArrayList<String> result_list = new ArrayList<String>();
        mDatabase = getReadableDatabase();
        //模糊查询的三种方式:
/*
 * 全部查询
        String current_sql_sel = "SELECT  * FROM " + tab_name;
        Cursor c = mDatabase.rawQuery(current_sql_sel, null);*/
         
        //1.使用这种query方法%号前不能加' ;
        Cursor c_test = mDatabase.query(tab_name, new String[]{tab_field02}, tab_field02+"  LIKE ? ",
                new String[] { "%" + str[0] + "%" }, null, null, null);
         
        //2.使用这种query方法%号前必须加'  ;
    //  Cursor  c_test=mDatabase.query(tab_name, new String[]{tab_field02},tab_field02+"  like '%" + str[0] + "%'", null, null, null, null);
     
        //3.使用这种方式必须在%号前加'  ;
        String current_sql_sel = "SELECT  * FROM "+tab_name +" where "+tab_field02+" like '%"+str[0]+"%'";
        //Cursor c_test = mDatabase.rawQuery(current_sql_sel, null);
         
         Log.e("tag", "查询完成...");
        while (c_test.moveToNext()) {
            String name = c_test.getString(c_test.getColumnIndex(tab_field02));
            //name.contains(str[0]);
            // 让集合中的数据不重复;
            if (!result_list.contains(name)) {
                result_list.add(name);
                 Log.e("tag", name);
            }
        }
        c_test.close();
 
        return result_list;
    }
 
}


转载请注明出处: http://blog.csdn.net/fth826595345/article/details/9199235

原文地址:https://www.cnblogs.com/jiangu66/p/3162937.html