bigquery 命令按位置拆分列

Question

How do I split a column by position in bigquery

Here I have a column with date of birth like this

19900311
20071103
19930802
19840130
19790206
19940301

I need to get only the year, so need to use substring function to get positions from 0,4

Could someone please help me with the correct command

Answer 1

Below is for BigQuery Standard SQL

You can use SUBSTR function as in below example

#standardSQL
WITH `project.dataset.table` AS (
  SELECT '19900311' date_of_birth UNION ALL
  SELECT '20071103' UNION ALL
  SELECT '19930802' UNION ALL
  SELECT '19840130' UNION ALL
  SELECT '19790206' UNION ALL
  SELECT '19940301' 
)
SELECT date_of_birth, SUBSTR(date_of_birth, 1, 4) year_of_birth
FROM `project.dataset.table`

with result

Row date_of_birth   year_of_birth    
1   19900311        1990     
2   20071103        2007     
3   19930802        1993     
4   19840130        1984     
5   19790206        1979     
6   19940301        1994