Regarding error in fast refresh for Materialized

Question

ORA-12015: cannot create a fast refresh materialized view from a complex query
CREATE MATERIALIZED VIEW CRESTELVIEWSDEV510.MVCONTENTHISTORY
TABLESPACE CRESTELVIEWSDEV510
NOCACHE
LOGGING
NOCOMPRESS
NOPARALLEL
BUILD IMMEDIATE
REFRESH FAST
ENABLE QUERY REWRITE
AS
SELECT a.DAY, a.contentname,
SUM
(CASE
WHEN (b.subscriptionstartdate) <= (a.DAY)
AND ((CASE
WHEN b.subscriptionenddate IS NOT NULL
THEN (a.DAY)
ELSE TO_DATE ('01/20/1990', 'MM/DD/YYYY')
END
) <=
(CASE
WHEN b.subscriptionenddate IS NOT NULL
THEN (b.subscriptionenddate)
ELSE TO_DATE ('01/20/1990', 'MM/DD/YYYY')
END
THEN 1
ELSE 0
END
) COUNT,
COUNT
(CASE
WHEN (b.subscriptionstartdate) <= (a.DAY)
AND ((CASE
WHEN b.subscriptionenddate IS NOT NULL
THEN (a.DAY)
ELSE TO_DATE ('01/20/1990', 'MM/DD/YYYY')
END
) <=
(CASE
WHEN b.subscriptionenddate IS NOT NULL
THEN (b.subscriptionenddate)
ELSE TO_DATE ('01/20/1990', 'MM/DD/YYYY')
END
THEN 1
ELSE 0
END
) cnt
FROM TBLTDATEWISECONTENT a,
(SELECT TRUNC (a.subscriptionstartdate) subscriptionstartdate,
TRUNC (a.subscriptionenddate) subscriptionenddate, b.NAME,
b.contentid
FROM syntbltcontentsubscrhistory a, syntblmcontent b
WHERE b.contentid = a.contentid(+)) b
WHERE a.contentid = b.contentid(+)
AND a.DAY = b.subscriptionstartdate(+)
GROUP BY a.contentname, a.DAY;
while creation time of this Materialized I have receive above error ORA-12015
I have also crated log with Primary on all base tables and index on column that is in where clause.
Kindly provide solution .
I want to create this MV with FAST Refresh.
Regards,
nayana chavda.

Answer 1

What's your Oracle version?
The error is pretty self explanatory. You can not build fast refresh MView with complex query.
check Oracle document,
http://download.oracle.com/docs/cd/B19306_01/server.102/b14226/repmview.htm#BABEEHGJ
To be fast refreshed, the defining query for a materialized view must observe certain restrictions. If you require a materialized view whose defining query is more general and cannot observe the restrictions, then the materialized view is complex and cannot be fast refreshed.
...