..
as
select IsNull(date,'') as date,
isnull(payment_type,'') as payment_type,
isnull(description,'') as Description,
isnull(paid_out,0) as paid_out,
isnull(paid_in,0) as Paid_in
from trans_details
where ac_number=@ac_number and
date between @beginning_date and @ending_date
order by date
as
select IsNull(date,'') as date,
isnull(payment_type,'') as payment_type,
isnull(description,'') as Description,
isnull(paid_out,0) as paid_out,
isnull(paid_in,0) as Paid_in
from trans_details
where ac_number=@ac_number and
date between @beginning_date and @ending_date
order by date
使用指定的替换值替换 NULL。语法
ISNULL ( check_expression , replacement_value ) 参数
check_expression将被检查是否为 NULL的表达式。check_expression 可以是任何类型的。replacement_value在 check_expression 为 NULL时将返回的表达式。replacement_value 必须与 check_expresssion 具有相同的类型。 返回类型
返回与 check_expression 相同的类型。注释
如果 check_expression 不为 NULL,那么返回该表达式的值;否则返回 replacement_value。示例
A. 将 ISNULL 与 AVG 一起使用
下面的示例查找所有书的平均价格,用值 $10.00 替换 titles 表的 price 列中的所有 NULL 条目。USE pubs
GO
SELECT AVG(ISNULL(price, $10.00))
FROM titles
GO下面是结果集:--------------------------
14.24 (1 row(s) affected)B. 使用 ISNULL
下面的示例为 titles 表中的所有书选择书名、类型及价格。如果一个书名的价格是 NULL,那么在结果集中显示的价格为 0.00。USE pubs
GO
SELECT SUBSTRING(title, 1, 15) AS Title, type AS Type,
ISNULL(price, 0.00) AS Price
FROM titles
GO下面是结果集:Title Type Price
--------------- ------------ --------------------------
The Busy Execut business 19.99
Cooking with Co business 11.95
You Can Combat business 2.99
Straight Talk A business 19.99
Silicon Valley mod_cook 19.99
The Gourmet Mic mod_cook 2.99
The Psychology UNDECIDED 0.00
But Is It User popular_comp 22.95
Secrets of Sili popular_comp 20.00
Net Etiquette popular_comp 0.00
Computer Phobic psychology 21.59
Is Anger the En psychology 10.95
Life Without Fe psychology 7.00
Prolonged Data psychology 19.99
Emotional Secur psychology 7.99
Onions, Leeks, trad_cook 20.95
Fifty Years in trad_cook 11.95
Sushi, Anyone? trad_cook 14.99
isnull(payment_type,'') as payment_type,
isnull(description,'') as Description,
isnull(paid_out,0) as paid_out,
isnull(paid_in,0) as Paid_in
where ac_number=@ac_number and
date between @beginning_date and @ending_date
order by date