Android数据库存储数据（Room、GreenDao、Sqlite）

目录

Android数据库存储数据（Room、GreenDao、Sqlite）

一、GreenDao的数据库框架：

二、Google的Room组件框架（参考官网学习地址：学习Room）：

1、AndroidStudio的gradle依赖：

2、实体类构造：

3、集成RoomDatabase的数据库：

4、Dao的操作类：

5、简单的使用：

三、Android Sqlite:

1、创建表的字段类：

2、Sqlite的Helpr类：

3、简单的增删改查工具类：

---

Android数据库存储数据（Room、GreenDao、Sqlite）

一、GreenDao的数据库框架：

去GreenDao的使用

二、Google的Room组件框架（参考官网学习地址：学习Room）：

1、AndroidStudio的gradle依赖：

//在 defaultConfig下配置该属性，那么创建的数据库的信息会在src的同目录下创建schemas文件夹        
javaCompileOptions {
            annotationProcessorOptions {
                arguments = ["room.schemaLocation": "$projectDir/schemas".toString()]
            }
        }

//=====================================================================

    implementation "android.arch.persistence.room:runtime:1.0.0"
    annotationProcessor "android.arch.persistence.room:compiler:1.0.0"

2、实体类构造：

package com.zbv.newdesttop.Entities;

import android.arch.persistence.room.ColumnInfo;
import android.arch.persistence.room.Entity;
import android.arch.persistence.room.PrimaryKey;

/**
 * author: qzx
 * Date: 2019/3/1 13:52
 */
@Entity
public class Person {
    @PrimaryKey(autoGenerate = true)
    public int id;

    @ColumnInfo(name = "first_name")
    public String firstName;
    @ColumnInfo(name = "last_name")
    public String lastName;
}

3、集成RoomDatabase的数据库：

package com.zbv.newdesttop.roomdao;

import android.arch.persistence.room.Database;
import android.arch.persistence.room.RoomDatabase;

import com.zbv.newdesttop.Entities.Person;

/**
 * author: qzx
 * Date: 2019/3/1 14:12
 */
@Database(entities = {Person.class}, version = 1)
public abstract class AppDatabase extends RoomDatabase {
    //要采取单例模式，因为每次创建会代价昂贵
    public abstract PersonDao personDao();
}

4、Dao的操作类：

package com.zbv.newdesttop.roomdao;

import android.arch.persistence.room.Dao;
import android.arch.persistence.room.Delete;
import android.arch.persistence.room.Insert;
import android.arch.persistence.room.Query;
import android.arch.persistence.room.Update;

import com.zbv.newdesttop.Entities.Person;

import java.util.List;

/**
 * author: qzx
 * Date: 2019/3/1 14:04
 */
@Dao
public interface PersonDao {

    @Query("SELECT * FROM person")
    public List getAll();

    @Query("SELECT * FROM person WHERE id in (:userIds)")
    public List getAllById(int[] userIds);

    @Query("SELECT * FROM person WHERE first_name LIKE :first AND last_name LIKE :last LIMIT 1")
    public Person findByName(String first, String last);

    @Update
    public void updateUsers(Person... person);

    @Insert
    public void insertAll(Person... person);

    @Delete
    public void delete(Person person);
}

5、简单的使用：

//如果操作数据库不开线程执行会报错，不能再主线程执行
//Cannot access database on the main thread since it may potentially lock the UI for a long period of time.
        AppDatabase appDatabase = Room.databaseBuilder(this, AppDatabase.class, "roomdao.db").build();
        personDao = appDatabase.personDao();

//添加数据
   new Thread(new Runnable() {
            @Override
            public void run() {
                Person person = new Person();
                person.firstName = "周";
                person.lastName = "尘";

                Person person_2 = new Person();
                person_2.firstName = "王";
                person_2.lastName = "福";
                personDao.insertAll(person, person_2);

                Log.e("zbv", "add complete...");
            }
        }).start();

//查询数据
  new Thread(new Runnable() {
            @Override
            public void run() {
                Log.e("zbv", "to query....");
                List ps = personDao.getAll();
                Log.e("zbv", "isNull?" + (ps == null) + ";size=" + ps.size());
                for (Person person : ps) {
                    Log.e("zbv", "id=" + person.id + ";firstName=" + person.firstName + ";lastName=" + person.lastName);
                }

            }
        }).start();

三、Android Sqlite:

1、创建表的字段类：

package com.zbv.newdesttop.database;

import android.provider.BaseColumns;

/**
 * author: qzx
 * Date: 2019/3/1 16:40
 */
public final class SqliteTables {
    private SqliteTables() {

    }

    public static class Customer implements BaseColumns {
        public static final String TABLE_NAME = "customer";
        public static final String COLUME_ONE = "name";
        public static final String COLUME_TWO = "address";
    }
}

2、Sqlite的Helpr类：

package com.zbv.newdesttop.database;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

/**
 * author: qzx
 * Date: 2019/2/28 14:35
 * 

 * sqlite本地数据库保存应用数据
 */
public class ZBVSqliteHelper extends SQLiteOpenHelper {

    // If you change the database schema, you must increment the database version.
    public static final int DATABASE_VERSION = 1;
    public static final String DATABASE_NAME = "sqlite.db";

    //主键自增
    private static final String SQL_CREATE_ENTRIES =
            "CREATE TABLE " + SqliteTables.Customer.TABLE_NAME + " (" +
                    SqliteTables.Customer._ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
                    SqliteTables.Customer.COLUME_ONE + " TEXT," +
                    SqliteTables.Customer.COLUME_TWO + " TEXT)";

    private static final String SQL_DELETE_ENTRIES =
            "DROP TABLE IF EXISTS " + SqliteTables.Customer.TABLE_NAME;

    public ZBVSqliteHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);

    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(SQL_CREATE_ENTRIES);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // This database is only a cache for online data, so its upgrade policy is
        // to simply to discard the data and start over
        db.execSQL(SQL_DELETE_ENTRIES);
        onCreate(db);
    }
}

3、简单的增删改查工具类：

package com.zbv.newdesttop.database;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.provider.BaseColumns;
import android.util.Log;

import com.zbv.newdesttop.Entities.Customer;

import java.util.ArrayList;
import java.util.List;

/**
 * author: qzx
 * Date: 2019/2/28 16:35
 * 

 * sqlite数据库操作，增删改查
 */
public class ZBVSqliteOperate {

    public static ZBVSqliteOperate zbvSqliteOperate = null;

    private ZBVSqliteHelper dbHelper;

    private ZBVSqliteOperate(Context context) {
        dbHelper = new ZBVSqliteHelper(context);
    }

    public static ZBVSqliteOperate getInstance(Context context) {
        if (zbvSqliteOperate == null) {
            synchronized (ZBVSqliteOperate.class) {
                if (zbvSqliteOperate == null) {
                    zbvSqliteOperate = new ZBVSqliteOperate(context);
                }
            }
        }
        return zbvSqliteOperate;
    }

    public void insert(Customer customer) {
        // Gets the data repository in write mode
        SQLiteDatabase database = dbHelper.getWritableDatabase();

        // Create a new map of values, where column names are the keys
        ContentValues values = new ContentValues();
        values.put(SqliteTables.Customer.COLUME_ONE, customer.getName());
        values.put(SqliteTables.Customer.COLUME_TWO, customer.getAddress());

        //第二个参数：If you specify null, like in this code sample, the framework does not insert a row when there are no values.
        long newRowId = database.insert(SqliteTables.Customer.TABLE_NAME, null, values);
    }

    public void delete(String column, String columnValue) {
        SQLiteDatabase db = dbHelper.getReadableDatabase();
        // Define 'where' part of query.
        String selection = column + " LIKE ?";
        // Specify arguments in placeholder order.
        String[] selectionArgs = {columnValue};
        // Issue SQL statement.
        int deletedRows = db.delete(SqliteTables.Customer.TABLE_NAME, selection, selectionArgs);
    }

    public void update(String column, String updateValue) {
        SQLiteDatabase db = dbHelper.getWritableDatabase();

        // New value for one column
        String title = "MyNewTitle";
        ContentValues values = new ContentValues();
        values.put(column, title);

        // Which row to update, based on the title
        String selection = column + " LIKE ?";
        String[] selectionArgs = {updateValue};

        int count = db.update(
                SqliteTables.Customer.TABLE_NAME,
                values,
                selection,
                selectionArgs);
    }

    public void query() {
        SQLiteDatabase db = dbHelper.getReadableDatabase();

        // Define a projection that specifies which columns from the database
        // you will actually use after this query.
        String[] projection = {
                BaseColumns._ID,
                SqliteTables.Customer.COLUME_ONE,
                SqliteTables.Customer.COLUME_TWO
        };

        // Filter results WHERE "title" = 'My Title'
        String selection = SqliteTables.Customer.COLUME_ONE + " = ?";
        String[] selectionArgs = {"七子笑"};

        // How you want the results sorted in the resulting Cursor
        String sortOrder =
                SqliteTables.Customer.COLUME_ONE + " DESC";

        Cursor cursor = db.query(
                SqliteTables.Customer.TABLE_NAME,   // The table to query
                projection,             // The array of columns to return (pass null to get all)
                selection,              // The columns for the WHERE clause
                selectionArgs,          // The values for the WHERE clause
                null,                   // don't group the rows
                null,                   // don't filter by row groups
                sortOrder               // The sort order
        );

        List itemIds = new ArrayList<>();
        while (cursor.moveToNext()) {
            long itemId = cursor.getLong(
                    cursor.getColumnIndexOrThrow(SqliteTables.Customer._ID));
            Log.e("zbv", "itemId=" + itemId);
            itemIds.add(itemId);
        }
        cursor.close();
    }

    /**
     * 关闭数据库
     */
    public void closeDB() {
        //Since getWritableDatabase() and getReadableDatabase() are expensive to call when the database is closed,
        // you should leave your database connection open for as long as you possibly need to access it
        if (dbHelper != null) {
            dbHelper.close();
        }
    }


}