爲什麼下面代碼中的@result值會打印出空白字符串?我希望它能和前面的結果連接起來。爲什麼這個TSql返回一個空值或空值?
DECLARE @size int
DECLARE @string nvarchar(10)
DECLARE @result nvarchar(10)
SELECT @string = '12345abc123'
DECLARE @count int, @total int
SELECT
@total = LEN(@string),
@count = 1
WHILE @count <= @total
BEGIN
SELECT @result = SUBSTRING(@string, @count, 1) + '-'+ @result
SELECT @count = @count + 1
PRINT @result
END