今天完成的事情：（一定要写非常细致的内容，比如说学会了盒子模型，了解了Margin）

学习多条件查询

多条件查询常用到Mybatis的if判断，这样只有条件满足时，才生成对应的SQL。  

<select id="selectUser" parameterType="map" resultMap="BaseResultMap">  

        select  

        <include refid="Base_Column_List" />  

        from user  

        <where>  

            <if test="name != null">  

                name = #{name,jdbcType=VARCHAR}  

            </if>  

            <if test="age != null">  

                and age = #{age,jdbcType=INTEGER}  

            </if>  

        </where>  

    </select>  

package org.example.controller;

import org.example.model.ApiResponse;
import org.example.model.Banner;
import org.example.model.Comment;
import org.example.service.BannerService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@RestController
@RequestMapping("/banner")
public class BannerController {
@Autowired
private BannerService bannerService;
    @GetMapping("/search")
    public ApiResponse<List<Banner>> queryBanner(String author, String state) {
        return ApiResponse.success(bannerService.getByCondition(author, state));
    }
@GetMapping("/all")
public ApiResponse <List<Banner>> getAllBanners() {
    List<Banner> banners = bannerService.getAllBanners();
    return ApiResponse.success(banners);
    }
    @PutMapping("/{id}")
    public ApiResponse<Map<String, Object>> updateBanner(@PathVariable Long id, @RequestBody Banner banner) {
        try {
            banner.setId(id);
            boolean success = bannerService.updateBanner(banner);
            if (success) {
                Map<String, Object> response = new HashMap<>();
                response.put("id", id);
                return ApiResponse.success(response);
            } else {
                return ApiResponse.error(500, "更新失败，请检查ID是否存在或字段是否有改动");
            }
        } catch (Exception e) {
            e.printStackTrace();
            return ApiResponse.error(400, "更新失败: " + e.getMessage());
        }
    }
    @PostMapping("/")
    public ApiResponse <Long> createBanner(@RequestBody Banner banner) {
        return ApiResponse.success(bannerService.insertBanner(banner));
    }
    @DeleteMapping("/{id}")
        public ApiResponse <Boolean> deleteBanner(@PathVariable Long id) {
    return ApiResponse.success(bannerService.deleteBanner(id));
    }
}

明天计划的事情：（一定要写非常细致的内容）
遇到的问题：（遇到什么困难，怎么解决的）
收获：（通过今天的学习，学到了什么知识）