Question

以下查询（精简版）有一个字符串需要强制转换为整数，但并非该字段中的所有条目都有值。 cast / case to int在语句的select部分工作正常，但在where语句中失败。我正在帮助一位同事并继续画一个空白，为什么这不起作用。有什么想法吗？

SELECT cast((case when item = ' ' then 0 else item end) as  int) as newNumber 
FROM tablename 
WHERE cast(trim(case when item = ' ' then 0 else item end) as INT) < 600

这是错误

Invalid character found in a character string argument of the function DECFLOAT

仅在添加 WHERE 语句时抛出错误。

Answer 1

WITH
  Q1 (ITEM) AS
     (VALUES ' ', '1', '2', '3', 'DFSDF', '601'),
  Q2 (ITEM) AS
     (SELECT INTEGER(CASE WHEN ITEM = ' ' THEN '0' ELSE ITEM END) AS NEWNUMBER
        FROM Q1
        WHERE TRIM(TRANSLATE(ITEM, '', '0123456789')) = '')
SELECT *
  FROM Q2
  WHERE Q2.ITEM < 600

DB2 Case / Cast in Where语句

1 个答案: