CREATE PROCEDURE get_sales_for_title
title varchar(80), @ytd_sales int OUTPUT
AS
SELECT @ytd_sales = ytd_sales
FROM titles
WHERE title = @title
IF @@ROWCOUNT = 0
RETURN(-1)
ELSE
RETURN(0)
另外建立了一个脚本执行这个存储过程，如果执行成功，将返回对应于书名的每天的销售情况的报表，如果执行失败，将返回“No Sales Found”，怎样建立这个脚本？
Ａ. DECLARE @retval int
DECLARE @ytd int
EXEC get_sales_for_title ‘Net Etiquette’, @ytd
IF @retval < 0
PRINT ‘No sales found’
ELSE
PRINT ‘Year to date sales: ’ + STR (@ytd)
GO
Ｂ. DECLARE @retval int
DECLARE @ytd int
EXEC get_sales_for_title ‘Net Etiquette’, @ytd OUTPUT
IF @retval < 0
PRINT ‘No sales found’
ELSE
PRINT ‘Year to date sales: ’ + STR (@ytd)
GO
Ｃ. DECLARE @retval int
DECLARE @ytd int
EXEC get_sales_for_title ‘Net Etiquette’,@retval OUTPUT
IF @retval < 0
PRINT ‘No sales found’
ELSE
PRINT ‘Year to date sales: ’ + STR (@ytd)
GO
Ｄ. DECLARE @retval int
DECLARE @ytd int
EXEC @retval = get_sales_for_title ‘Net Etiquette’, @ytd OUTPUT
IF @retval < 0
PRINT ‘No sales found’
ELSE
PRINT ‘Year to date sales: ’ + STR (@ytd)
GO
参考答案