子查询出错，哪个大神帮忙看下

Question

错误提示：Statement 1 is not valid. ORA-00923: FROM keyword not found where expectedSELECT
a.1015ID AS "ShipmentID"
, TO_DATE(a.1015DateTime,'YYYY/MM/DD HH24:MI:SS') AS "15Datetime"
, TO_DATE(b.1007DateTime,'YYYY/MM/DD HH24:MI:SS') AS "07Datetime"
FROM
(
SELECT
x.SHIPMENT_ID AS "1015ID"
,TO_DATE(x.EVENT_DATETIME,'YYYY/MM/DD HH24:MI:SS') AS "1015DateTime"
FROM
ORDER_PIPELINE_EVENTS x
WHERE
x.OLD_EVENT_CD ='1004' 
and x.NEW_EVENT_CD ='1015' 
and x.REGION_ID = 3 
and x.WAREHOUSE_ID = 'SHA2' 
and x.EVENT_DAY =TO_DATE('{RUN_DATE_YYYYMMDD}','YYYY/MM/DD') - 1
) a
,
(
SELECT
y.SHIPMENT_ID AS "1007ID"
,TO_DATE(y.EVENT_DATETIME,'YYYY/MM/DD HH24:MI:SS') AS "1007DateTime"
FROM
ORDER_PIPELINE_EVENTS y
WHERE
y.OLD_EVENT_CD ='1015' 
and y.NEW_EVENT_CD ='1007' 
and y.REGION_ID = 3 
and y.WAREHOUSE_ID = 'SHA2' 
and y.EVENT_DAY =TO_DATE('{RUN_DATE_YYYYMMDD}','YYYY/MM/DD') - 1
) b
ON 
WHERE
a.1015ID = b.1007ID
子查询subquery

Answer 1

a.1015ID AS "ShipmentID"
---------------------------
a."1015ID"  "ShipmentID"