android sqlite数据库 创建表

创建表的语句很简单,格式如下
create table 表名(字段名 类型,字段名 类型,…);

package com.uyac.andriodsqlite;

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

/**
 * Created by ShaoQuanwei on 2017/2/15.
 */

public class MySqliteHelper extends SQLiteOpenHelper {

    /*表名*/
    private final String TABLE_NAME_PERSON = "person";
    /*id字段*/
    private final String VALUE_ID = "_id";
    private final String VALUE_NAME = "name";
    private final String VALUE_ISBOY = "isboy";
    private final String VALUE_AGE = "age";
    private final String VALUE_ADDRESS = "address";
    /*头像字段*/
    private final String VALUE_PIC = "pic";

    /*创建表语句 语句对大小写不敏感 create table 表名(字段名 类型,字段名 类型,…)*/
    private final String CREATE_PERSON = "create table " + TABLE_NAME_PERSON + "(" +
            VALUE_ID + " integer primary key," +
            VALUE_NAME + " text ," +
            VALUE_ISBOY + " integer," +
            VALUE_AGE + " ingeter," +
            VALUE_ADDRESS + " text,"+
            VALUE_PIC + " blob"+
            ")";


    public MySqliteHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {
        super(context, name, factory, version);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {

        //创建表
        db.execSQL(CREATE_PERSON);

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }
}

mySqliteHelper = new MySqliteHelper(context,Constants.DB_NAME,null,Constants.DB_VERSION);

当你new了之后,添加第一条数据时,才可以在data/data/包名/databases目录下面可以发现你创建的数据库名和表名。

  • 当首次安装时
02-17 10:41:01.187 25862-25862/com.uyac.andriodsqlite E/MySqliteHelper: -------> MySqliteHelper
02-17 10:41:01.480 25862-25862/com.uyac.andriodsqlite E/MySqliteHelper: -------> onCreate
  • 当再次启动数据库版本保持不变时
02-17 10:45:52.976 29607-29607/com.uyac.andriodsqlite E/MySqliteHelper: -------> MySqliteHelper
  • 当再次安装数据库版本升级时
02-17 10:41:59.286 27082-27082/com.uyac.andriodsqlite E/MySqliteHelper: -------> MySqliteHelper
02-17 10:41:59.421 27082-27082/com.uyac.andriodsqlite E/MySqliteHelper: -------> onUpgrade

sqlite也无非就创建、增、删、改、查、更新。

    原文作者:duoduo7628
    原文地址: https://www.jianshu.com/p/394571ebbb42
    本文转自网络文章,转载此文章仅为分享知识,如有侵权,请联系博主进行删除。
点赞