以下是我的表格摘录:
gid | datepose | pvc
---------+----------------+------------
1 | 1961 | 01
2 | 1949 |
3 | 1990 | 02
1 | 1981 |
1 | | 03
1 | |
我想用SELECT CASE
填充PVC柱,如下所示:
SELECT
gid,
CASE
WHEN (pvc IS NULL OR pvc = '') AND datpose < 1980) THEN '01'
WHEN (pvc IS NULL OR pvc = '') AND datpose >= 1980) THEN '02'
WHEN (pvc IS NULL OR pvc = '') AND (datpose IS NULL OR datpose = 0) THEN '03'
END AS pvc
FROM my_table ;
结果与源表的内容相同,没有发生任何事情,并且在pg_日志(log)文件中没有收到错误消息.这可能是语法错误,或者是在WHEN子句中使用多个条件的问题?
谢谢你的帮助和建议!