你的部门负责从 SQL Server 2005 数据库中的数据创建客户电子邮件地址列表。此列表必须包含上次联系每个客户的日期。 结果集中的数据必须有列名。 列表必须以上次联系客户的日期排序,最近联系的人排在前边。LastContact 列以 datetime 类型存储。日期应以MM/
你的部门负责从 SQL Server 2005 数据库中的数据创建客户电子邮件地址列表。此列表必须包含上次联系每个客户的日期。 结果集中的数据必须有列名。 列表必须以上次联系客户的日期排序,最近联系的人排在前边。LastContact 列以 datetime 类型存储。日期应以MM/DD/YYYY 的形式显示。 一位同事设计了以下查询:SELECT email_address AS EmailAddress, CONVERT(nvarchar, lastcontact, 101) AS LastContact FROM Contact ORDER BY LastContact DESC.
你测试了此查询,并发现数据按如下顺序显示:
EmailAddress LastContact
andrew@contoso.com 01/24/2003
marc@contoso.com 06/12/2005
stefan@contoso.com 07/13/2004
你需要修改此查询以使数据按正确的顺序排列。 你想要对性能不造成任何负面影响而达成此目标,该怎样做?
SELECT email_address AS EmailAddress, CONVERT(nvarchar, lastcontact, 101) AS Last_Contact FROM Contact ORDER BY lastcontact DESC

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