02.TK.Mybatis之Select

TK.Mybatis查詢方法

一、概述

本章節基於第一章節的：01.Mybatis Tk插件環境搭建
TK的內置查詢方法有很多，在該章節主要介紹幾種常用的的方法：

selectAll()：查詢所有
selectByPrimaryKey(Object var1)：主鍵查詢
selectByExample(Example example)：用來複雜查詢

二、單元測試

主鍵查詢
它會根據主鍵進行查詢，進行傳的是一個對象，它只會拼接主鍵。

	@Test
    public void selectAll(){
        Product param = new Product();
        param.setId(1L);
        param.setProductName("Redis深度歷險記");
        //Product product = productDao.selectByPrimaryKey(1L);  等價下面語句
        Product product = productDao.selectByPrimaryKey(param);
    }
 //==>  Preparing: SELECT id,product_name,price,in_time,out_time FROM product WHERE id = ?
//==> Parameters: 1(Long)
//<==    Columns: id, product_name, price, in_time, out_time
//<==        Row: 1, Redis深度歷險記, 79, 2019-12-21 18:22:20, 2019-12-23 18:22:20
//<==      Total: 1

複雜查詢-1：範圍查詢
比如：我要查詢入庫時間在：2019-12-19—2019-12-25的商品

@Test
    public void selectBetWeen(){
        Example example = new Example(Product.class);
        
        LocalDateTime from = LocalDateTime.of(2019,12,19,0,0);
        LocalDateTime to = LocalDateTime.of(2019, 12, 26,0,0);

        example.createCriteria().andBetween("inTime", from, to);
        List<Product> products = productDao.selectByExample(example);
    }
    
//==>  Preparing: SELECT id,product_name,price,in_time,out_time FROM //product WHERE ( in_time between ? and ? ) 
//==> Parameters: 2019-12-19 00:00:00.0(Timestamp), 2019-12-26 //00:00:00.0(Timestamp)
//<==    Columns: id, product_name, price, in_time, out_time
//<==        Row: 1, Redis深度歷險記, 79, 2019-12-21 18:22:20, 2019-12-23 //18:22:20
//<==        Row: 2, Java 8 函數編程, 56, 2019-12-24 18:22:20, 2019-12-26 //18:22:20
//<==      Total: 2

複雜查詢-2：多條件查詢比如：（a or b） and ( c )
在這裏，我要查詢入庫時間大於等2019-12-25，且出庫時間大於等與2019-12-25的商品。

	@Test
    public void selectByCra(){
        Example example = new Example(Product.class);

        //LocalDateTime cur = LocalDateTime.of(2019,12,25,0,0);
        
        Example.Criteria c = example.createCriteria();
        c.andLessThanOrEqualTo("inTime", "2019-12-25 00:00:00.0");

        Example.Criteria e = example.createCriteria();
        e.andGreaterThanOrEqualTo("outTime", "2019-12-25 00:00:00.0");

        example.and(e);
        List<Product> products = productDao.selectByExample(example);
    }
    
//==>  Preparing: SELECT id,product_name,price,in_time,out_time FROM //product WHERE ( in_time <= ? ) and ( out_time >= ? ) 
//==> Parameters: 2019-12-25T00:00(String), 2019-12-25T00:00(String)
//<==    Columns: id, product_name, price, in_time, out_time
//<==        Row: 2, Java 8 函數編程, 56, 2019-12-24 18:22:20, 2019-12-26 //18:22:20
//<==      Total: 1