BigQuery 是否允许使用 SQL
with
子句进行多表连接?
例子:
WITH t1 as (select tab1, tab2 from t1 group by 1,2),
t2 as ( select tab1, tab2, tab3, from t2 group by 1,2,3)
t3 as ( select tab1, tab2, from t3 group by 1,2,3)
我可以通过多次重复相同的查询来使下面的查询工作,但不想,并且想利用它
with as
:
SELECT a.tab1, a.tab2, b.tab1, b. tab3, c.tab1, c.tab2
FROM t1 a
LEFT JOIN t2 b
ON a.tabl = b.tab1 and a.tab2 = b.tab3
LEFT JOIN t3 c
ON a.tab1 = c.tab1
SELECT a.tab1, a.tab2, b.tab1, b. tab3, c.tab1, c.tab2
FROM t1 a
LEFT JOIN t2 b
ON a.tabl = b.tab1 and a.tab2 = b.tab3
LEFT JOIN t3 c
ON a.tab1 = c.tab1