修改推荐图书

src/main/java/com/peanut/modules/bookAbroad/controller/HomeController.java

@@ -78,6 +78,7 @@ public class HomeController {
         //查询已购买图书
         LambdaQueryWrapper<UserEbookBuyEntity> wrapper = new LambdaQueryWrapper<>();
         wrapper.eq(UserEbookBuyEntity::getUserId,ShiroUtils.getUId());
+        wrapper.select(UserEbookBuyEntity::getBookId);
         wrapper.groupBy(UserEbookBuyEntity::getBookId);
         Set<Integer> bookIds = userEbookBuyService.getBaseMapper().selectList(wrapper).stream()
                 .map(UserEbookBuyEntity::getBookId).collect(Collectors.toSet());