diff --git a/src/main/java/neatlogic/framework/process/dao/mapper/PriorityMapper.xml b/src/main/java/neatlogic/framework/process/dao/mapper/PriorityMapper.xml
index 85485ff24b99a3dacd3253e4cbfe7c93b47560d7..5de281f3d3e0801c20b21ffe707409dabe31d32b 100644
--- a/src/main/java/neatlogic/framework/process/dao/mapper/PriorityMapper.xml
+++ b/src/main/java/neatlogic/framework/process/dao/mapper/PriorityMapper.xml
@@ -102,15 +102,15 @@
 								OR `${filter.uuid}` IS NULL)
 							</when>
 							<otherwise>
-								(`${filter.uuid}` NOT LIKE CONCAT('%', #{filter.valueList[0]}, '%') OR a.`${filter.uuid}` IS NULL)
+								(`${filter.uuid}` NOT LIKE CONCAT('%', #{filter.valueList[0]}, '%') OR `${filter.uuid}` IS NULL)
 							</otherwise>
 						</choose>
 					</when>
 					<when test="filter.expression == 'is-null'">
-						`${filter.uuid}` IS NULL
+						(`${filter.uuid}` IS NULL OR `${filter.uuid}` = '')
 					</when>
 					<when test="filter.expression == 'is-not-null'">
-						`${filter.uuid}` IS NOT NULL
+						(`${filter.uuid}` IS NOT NULL AND `${filter.uuid}` != '')
 					</when>
 					<otherwise>
 						<choose>