在SELECT结果中将空/ NULL结果替换为“ FALSE”

Question

我需要知道当值返回为空或null时是否可以用字符串“ FALSE”替换SELECT的结果？谢谢

Answer 1

您可以在以下情况下使用大小写

select case when COL_NAME is null  OR LENGTH(TRIM (COL_NAME)) = 0 then 'False' 
           else COL_NAME end
       from table_name

Answer 2

您正在寻找凉粉。

SELECT COALESCE(COL_NAME, 'False') AS COL_NAME FROM table_name

Answer 3

SELECT CASE WHEN COLUMN IS NULL OR COLUMN '' THEN 'FALSE' ELSE COLUMN END FROM TABLE_NAME