update

edu-user/edu-user-server/src/main/resources/config/mybatis/SubjectMapper.xml

@@ -108,6 +108,9 @@
             <if test="parentId != null">
                 AND parent_subject_id_ = #{parentId}
             </if>
+            <if test="parentId == null">
+                AND parent_subject_id_ != 0
+            </if>
             <if test="tenantId != null">
                 AND tenant_id_ = #{tenantId}
             </if>