在 Big Query 中查询多个表 [英] Querying multiple tables in Big Query

问题描述

由于无法在 BigQuery 中更新表内的数据，并且仅支持追加机制，因此我决定按月创建新表.所以假设 2012 年的表是 (tbl_012012, tbl_022012, tbl_032012,...tbl_122012).每条记录将与日期 timestamp 一起存储为字符串.

As it is not possible to update data within a table in BigQuery, and supports only append mechanism, I have decided to create new tables on monthly basis. So suppose for year 2012 the tables would be (tbl_012012, tbl_022012, tbl_032012,...tbl_122012). Each record will be stored along with date timestamp as string.

现在，如果我的应用程序想要获取从 2012 年 1 月(tbl_012012) 到 2012 年 3 月(tbl_032012) 的记录，BigQuery API 是否会通过以下方式自动遍历所需的表单个 SQL 范围查询还是我必须使用额外的应用程序代码编写多个 SQL 查询来检索每个查询结果，然后将它们聚合在一起?

Now, if my application wants to fetch records ranging from Jan 2012(tbl_012012) to March 2012(tbl_032012), will BigQuery API automatically traverse through the desired tables via single SQL range query or will I have to write multiple SQL queries with extra application code to retrieve each query result and then aggregate them altogether?

推荐答案

一个 SQL 查询可以引用多个表.只需在 FROM 子句中用逗号分隔每个表即可查询所有提到的表.

One SQL query can reference multiple tables. Just separate each table with a comma in the FROM clause to query across all mentioned tables.

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