这条sql语句我要怎样优化才能使其查询速度在1秒之内呀！小弟急

T08_PARTY_RESULT 数据将近240万 T47_PARTY数据量为240万 T08_DEF_TMPL 表的数据为200条

SELECT COUNT(*) FROM T08_PARTY_RESULT A,T08_DEF_TMPL B,T47_PARTY C WHERE A.TEMPLATEKEY=B.TEMPLATEKEY AND C.PARTY_ID=A.PARTY_ID AND A.ORGANKEY IN(',',.......);

下面是执行计划
SELECT STATEMENT, GOAL = CHOOSE Cost=6078 Cardinality=1 Bytes=32
SORT AGGREGATE Cardinality=1 Bytes=32
NESTED LOOPS Cost=6078 Cardinality=2356980 Bytes=75423360
HASH JOIN Cost=6078 Cardinality=2356980 Bytes=58924500
INDEX FAST FULL SCAN Object name=PK_T47_PARTY Cost=776 Cardinality=2438728 Bytes=17071096
TABLE ACCESS FULL Object name=T08_PARTY_RESULT Cost=3523 Cardinality=2356980 Bytes=42425640
INDEX UNIQUE SCAN Object name=PK_T08_DEF_TMPL Cardinality=1 Bytes=7