Error cannot generate SQL for Custom SQL at BO - sql

Question

I'm using business object 4 and currently developing a report using custom SQL. Total object and data type selected using custom sql and object at webbi already the same. But when I try to validate webbi always sends error cannot generate sql.
How to fix this and what is the cause of this error?
My sql syntax is as follows:
select * from(
SELECT
DISTINCT
CASE WHEN TRIM(msv26A.PROJECT_NO) IS NULL THEN msvPRJ.PROJECT_NO ELSE msv26A.PROJECT_NO END,
msv660.PROJ_DESC,
msv26A.PO_NO,
msv200.SUPPLIER_NAME,
msv26A.SUPPLIER_NO,
msv260.EXT_INV_NO,
msv200.SUP_TYPEX1,
msv260.CURRENCY_TYPE,
msv000_DC0001.DSTRCT_CODE,
msv000_DC0001.DSTRCT_NAME,
msv260.PMT_STATUS,
msv260.DUE_DATE,
msv260.INV_DATE,
msv260.FOR_INV_ORIG,
msv260.LOC_INV_ORIG,
msv260.FOR_INV_AMD,
msv260.LOC_INV_AMD,
msv260.AMT_RETAINED,
msv260.PRESC_PMT_AMT,
msv260.PP_AMT_LOC,
msv260_1.AMT_PAID_FOR,
msv071.REF_CODE,
CASE WHEN EMV260_AGING_RETENTION.LOC_INV_RETENTION IS NULL THEN 0 ELSE EMV260_AGING_RETENTION.LOC_INV_RETENTION END,
CASE WHEN EMV260_AGING_RETENTION.FOR_INV_RETENTION IS NULL THEN 0 ELSE EMV260_AGING_RETENTION.FOR_INV_RETENTION END
FROM
msv200 RIGHT OUTER JOIN msv26A ON (msv26A.SUPPLIER_NO = msv200.SUPPLIER_NO)
INNER JOIN msv000_DC0001 ON (msv000_DC0001.DSTRCT_CODE = msv26A.DSTRCT_CODE)
INNER JOIN msv260 ON (msv26A.DSTRCT_CODE = msv260.DSTRCT_CODE AND msv26A.SUPPLIER_NO = msv260.SUPPLIER_NO AND msv26A.INV_NO = msv260.INV_NO)
LEFT OUTER JOIN msvPRJ ON (msvPRJ.DSTRCT_CODE = msv26A.DSTRCT_CODE AND TRIM(msvPRJ.PO_NO) = trim(msv26A.PO_NO))
LEFT OUTER JOIN msv660 ON (msv26A.DSTRCT_CODE = msv660.DSTRCT_CODE AND (CASE WHEN TRIM(msv26A.PROJECT_NO) IS NULL
THEN msvPRJ.PROJECT_NO ELSE msv26A.PROJECT_NO END) = msv660.PROJECT_NO)
LEFT OUTER JOIN msv260 msv260_1 ON (msv260_1.DSTRCT_CODE = msv260.DSTRCT_CODE and msv260_1.SUPPLIER_NO = msv260.SUPPLIER_NO and msv260_1.INV_NO = msv260.INV_NO)
LEFT OUTER JOIN msv071 ON (msv071.ENTITY_VALUE=msv260.SUPPLIER_NO AND msv071.ENTITY_TYPE='SUP')
LEFT OUTER JOIN (SELECT A.DSTRCT_CODE,
A.SUPPLIER_NO,
A.ORIG_INV_NO,
SUM(CASE WHEN A.LOC_INV_AMD <> 0
THEN A.LOC_INV_AMD ELSE A.LOC_INV_ORIG END) LOC_INV_RETENTION,
SUM(CASE WHEN A.FOR_INV_AMD <> 0
THEN A.FOR_INV_AMD ELSE A.FOR_INV_ORIG END) FOR_INV_RETENTION
FROM msv260 A
WHERE A.FULL_PER_LOADED <= #prompt('Enter Full Period(From):','A','260\Full Per Loaded',Mono,Free,Persistent,,User :3)
AND TRIM(A.PMT_STATUS) >= '30' AND TRIM(A.PMT_STATUS) <= '55'
GROUP BY
A.DSTRCT_CODE,
A.SUPPLIER_NO,
A.ORIG_INV_NO) EMV260_AGING_RETENTION
ON (msv260.DSTRCT_CODE = EMV260_AGING_RETENTION.DSTRCT_CODE
AND msv260.SUPPLIER_NO = EMV260_AGING_RETENTION.SUPPLIER_NO
AND msv260.INV_NO = EMV260_AGING_RETENTION.ORIG_INV_NO)
WHERE
msv26A.DSTRCT_CODE in #prompt('Enter value(s) for Dstrct Code:','A','msv26a\Dstrct Code',Multi,Free,Persistent,,User:5)
AND
TRIM(msv260.PMT_STATUS) >= '30' AND TRIM(msv260.PMT_STATUS) <= '55'
AND
(
( msv260.FULL_PER_LOADED <= #prompt('Enter Full Period(From):','A','260\Full Per Loaded',Mono,Free,Persistent,,User :3)
AND msv260.FULL_PER_PAID = '000000' )
OR
( msv260.FULL_PER_PAID > #prompt('Enter Full Period(To):','A','260\Full Per Paid',Mono,Free,Persistent,,User :4)
AND msv260.FULL_PER_LOADED <= #prompt('Enter Full Period(From):','A','260\Full Per Loaded',Mono,Free,Persistent,,User :3) )
)
AND msv260.CURRENCY_TYPE <> ' '
ORDER BY msv000_DC0001.DSTRCT_CODE, msv260.SUPPLIER_NO, msv200.SUP_TYPEX1, msv260.CURRENCY_TYPE)
WHERE (DSTRCT_CODE,SUPPLIER_NO,EXT_INV_NO) IN (SELECT
DISTINCT DSTRCT_CODE,SUPPLIER_NO,EXT_INV_NO FROM msv900
WHERE DSTRCT_CODE in #prompt('Enter value(s) for Dstrct Code:','A','msv900\Dstrct Code',Multi,Free,Persistent,,User:1)
AND FULL_PERIOD <= #prompt('Enter Full Period(From):','A','msv900\Full Period',Mono,Free,Persistent,,User :2)
AND ACCOUNT_CODE IN ('21101')
)
ORDER BY
PROJECT_NO,
SUPPLIER_NO