[英]Count not null in sql
I have a table A
with column data:我有一个包含列数据的表
A
:
mdr1222
-------
pprgd24
-------
invalid
-------
invalid
abc2345
I want to get a count of the invalid and blank(---).我想获得无效和空白(---)的计数。 I tried :
我试过 :
SELECT count(data)
from A
where data = 'invalid' and null
but it doesn't work.但它不起作用。 Can someone please help me figure out what I am doing wrong here?
有人可以帮我弄清楚我在这里做错了什么吗?
This should work as well.这也应该有效。
SUM(CASE WHEN data IS NULL OR data = 'Invalid' THEN 1 ELSE 0 END)
FROM A
select count(column_name) from table_name where column_name is not null
returns number of rows where column_name
value is not null
返回
column_name
值不为null
的行数
select count(column_name) from table_name where column_name is null
returns number of rows where column_name
value is null
返回
column_name
值为null
的行数
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.