_TABLE_SUFFIX在多個連接上

Question

在BigQuery中，標準SQL如何在多個表上使用_TABLE_SUFFIX？看例子：

select * 
from `table1.*` t1 
left join `table2.*` t2 on t1.lel=t2.lel 
where _TABLE_SUFFIX between '2017-01-01' and '2017-01-02' <--- this can't be used 

我是否有義務創建table_suffix的子查詢應用於它首先？

Answer 1

在您的查詢中_TABLE_SUFFIX不明確，因爲BigQuery無法判斷它是來自t1還是t2。你可以用明確的前綴t1.或t2.它的歧義，即

select * 
from `table1.*` t1 
left join `table2.*` t2 on t1.lel=t2.lel 
where t1._TABLE_SUFFIX between '2017-01-01' and '2017-01-02'