diff --git a/src/main/resources/sql/mapper/epost/emailResult-mapper.xml b/src/main/resources/sql/mapper/epost/emailResult-mapper.xml
index 73a2c9b..c615dab 100644
--- a/src/main/resources/sql/mapper/epost/emailResult-mapper.xml
+++ b/src/main/resources/sql/mapper/epost/emailResult-mapper.xml
@@ -9,7 +9,7 @@
 
 <insert id="insertReceptionResult"  parameterType="cokr.xit.interfaces.epost.ReceptionResult">/* 전자우편 신청 수신 결과 등록(emailResultMapper.insertReceptionResult) */
 <selectKey resultType="string" keyProperty="rcptnRsltId" order="BEFORE">
-SELECT IFNULL(MAX(RCPTN_RSLT_ID) + 1, CONCAT(TODAY, '0000001')) NEW_ID
+SELECT NVL(MAX(RCPTN_RSLT_ID) + 1, CONCAT(TODAY, '0000001')) NEW_ID
   FROM TB_EPOST_RCPTN_RSLT A, (<include refid="utility.selectToday" />) B
  WHERE RCPTN_RSLT_ID LIKE CONCAT(TODAY, '%')</selectKey>
 INSERT INTO TB_EPOST_RCPTN_RSLT (
@@ -53,7 +53,7 @@ SELECT #{rcptnRsltId}  <!-- 수신 결과 ID -->
 
 <insert id="insertRegistrationResult" parameterType="cokr.xit.interfaces.epost.RegistrationResult">/* 전자우편 신청 접수 결과 등록(emailResultMapper.insertRegistrationResult) */
 <selectKey resultType="string" keyProperty="rcptRsltId" order="BEFORE">
-SELECT IFNULL(MAX(RCPT_RSLT_ID) + 1, CONCAT(TODAY, '0000001')) NEW_ID
+SELECT NVL(MAX(RCPT_RSLT_ID) + 1, CONCAT(TODAY, '0000001')) NEW_ID
   FROM TB_EPOST_RCPT_RSLT A, (<include refid="utility.selectToday" />) B
  WHERE RCPT_RSLT_ID LIKE CONCAT(TODAY, '%')</selectKey>
 INSERT INTO TB_EPOST_RCPT_RSLT (
@@ -129,7 +129,7 @@ SELECT #{conKey}      <!-- 외부연계식별키 -->
 
 <insert id="insertDeliveryResult" parameterType="cokr.xit.interfaces.epost.DeliveryResult">/* 전자우편 배달 결과 등록(emailResultMapper.insertDeliveryResult) */
 <selectKey resultType="string" keyProperty="dlvrRsltId" order="BEFORE">
-SELECT IFNULL(MAX(DLVR_RSLT_ID) + 1, CONCAT(TODAY, '0000001')) NEW_ID
+SELECT NVL(MAX(DLVR_RSLT_ID) + 1, CONCAT(TODAY, '0000001')) NEW_ID
   FROM TB_EPOST_DLVR_RSLT A, (<include refid="utility.selectToday" />) B
  WHERE DLVR_RSLT_ID LIKE CONCAT(TODAY, '%')</selectKey>
 INSERT INTO TB_EPOST_DLVR_RSLT (