BigQuery 根据条件连接表

Question

Table 否 1:

Table 否 2:

结果

 I have 2 Table :
    In table 1 column Name is unique identifier and also in Table 2 column Name is unique identifier 

Based on Table 2 ,column : Name I want to get data from Table 1 then I want to map the column tags on which date it is applied in Table2 column Date. 
As in table 2 , column : name , value :ghi , Date : 2/4/2022 tag was applied but in table 1 we have a cost for 2/1/2022 and 2/4/2022. so in result i will say on 2/1/2022 (no set) and after we give its value.

Answer 1

因此您可以使用如下查询

select 
t1.date, 
t1.Name, 
t1.cost,
IFNULL(t2.tags,'(not set)')
 from table1 t1 left outer join
table2 t2 on t1.name=t2.name and t1.date>=t2.date

BigQuery 根据条件连接表

BigQuery Join tables based on condition

sql

google-bigquery