feat: bug修复

qing-yu-club-subject/qing-yu-club-infra/src/main/resources/mapper/SubjectCategoryDao.xml

@@ -105,6 +105,13 @@
             </if>
         </where>
     </select>
+    <select id="querySubjectCount" resultType="java.lang.Integer">
+        select count(distinct subject_id)
+        from subject_mapping a,
+             subject_label b
+        where a.label_id=b.id
+        and b.category_id=#{id}
+    </select>
 
     <!--新增所有列-->
     <insert id="insert" keyProperty="id" useGeneratedKeys="true">