复杂关联查询物化视图

复杂关联查询物化视图

实现目标：查询子表TEST_B的STATUS为1的记录所关联的父表的CODE

1、现在子表建立聚合物化视图
CREATE MATERIALIZED VIEW LOG on test_b WITH rowid ,SEQUENCE (status,p_id) INCLUDING NEW VALUES;

create materialized view mv_test_b  
 BUILD immediate
 refresh fast on demand  
 start with sysdate next sysdate+1/1440 with rowid  
 as 
 select a.p_id,COUNT(*) from test_b a where a.status=1 group by a.p_id;
 
 
2、在子表聚合物化视图上建立日志
CREATE MATERIALIZED VIEW LOG on mv_test_b WITH rowid ,SEQUENCE (p_id) INCLUDING NEW VALUES;

3、在主表建立关联物化视图和日志
CREATE MATERIALIZED VIEW LOG on test_a WITH rowid ,SEQUENCE (code) INCLUDING NEW VALUES;

create materialized view mv_test_code  
 BUILD immediate
 refresh fast on demand  
 start with sysdate next sysdate+1/1440 with rowid  
 as 
 select  b.code,a.rowid aid,b.rowid bid from mv_test_b a, test_a b where a.p_id=b.id;