1)我不知道这是否是一个“官方的”反模式，但我不喜欢并试图避免在数据库列中使用字符串文字作为魔法值。

MediaWiki表'image'中的一个例子:

img_media_type ENUM("UNKNOWN", "BITMAP", "DRAWING", "AUDIO", "VIDEO", 
    "MULTIMEDIA", "OFFICE", "TEXT", "EXECUTABLE", "ARCHIVE") default NULL,
img_major_mime ENUM("unknown", "application", "audio", "image", "text", 
    "video", "message", "model", "multipart") NOT NULL default "unknown",

(我只是注意到不同的大小写，另一个要避免的事情)

我设计了这样的情况，int查找表ImageMediaType和ImageMajorMime与int主键。

2)日期/字符串转换，依赖于特定的NLS设置

CONVERT(NVARCHAR, GETDATE())

没有格式标识符

像这样将冗余表连接到查询中:

select emp.empno, dept.deptno
from emp
join dept on dept.deptno = emp.deptno;

The Altered View - A view that is altered too often and without notice or reason. The change will either be noticed at the most inappropriate time or worse be wrong and never noticed. Maybe your application will break because someone thought of a better name for that column. As a rule views should extend the usefulness of base tables while maintaining a contract with consumers. Fix problems but don't add features or worse change behavior, for that create a new view. To mitigate do not share views with other projects and, use CTEs when platforms allow. If your shop has a DBA you probably can't change views but all your views will be outdated and or useless in that case. The !Paramed - Can a query have more than one purpose? Probably but the next person who reads it won't know until deep meditation. Even if you don't need them right now chances are you will, even if it's "just" to debug. Adding parameters lowers maintenance time and keep things DRY. If you have a where clause you should have parameters. The case for no CASE - SELECT CASE @problem WHEN 'Need to replace column A with this medium to large collection of strings hanging out in my code.' THEN 'Create a table for lookup and add to your from clause.' WHEN 'Scrubbing values in the result set based on some business rules.' THEN 'Fix the data in the database' WHEN 'Formating dates or numbers.' THEN 'Apply formating in the presentation layer.' WHEN 'Createing a cross tab' THEN 'Good, but in reporting you should probably be using cross tab, matrix or pivot templates' ELSE 'You probably found another case for no CASE but now I have to edit my code instead of enriching the data...' END

回复:使用@@IDENTITY代替SCOPE_IDENTITY()

两者都不能用;使用输出代替

参见https://connect.microsoft.com/SQLServer/feedback/details/328811/scope-identity-sometimes-returns-incorrect-value

我一直对大多数程序员倾向于在数据访问层混合他们的ui逻辑感到失望:

SELECT
    FirstName + ' ' + LastName as "Full Name",
    case UserRole
        when 2 then "Admin"
        when 1 then "Moderator"
        else "User"
    end as "User's Role",
    case SignedIn
        when 0 then "Logged in"
        else "Logged out"
    end as "User signed in?",
    Convert(varchar(100), LastSignOn, 101) as "Last Sign On",
    DateDiff('d', LastSignOn, getDate()) as "Days since last sign on",
    AddrLine1 + ' ' + AddrLine2 + ' ' + AddrLine3 + ' ' +
        City + ', ' + State + ' ' + Zip as "Address",
    'XXX-XX-' + Substring(
        Convert(varchar(9), SSN), 6, 4) as "Social Security #"
FROM Users

通常，程序员这样做是因为他们想要将数据集直接绑定到一个网格上，而且在服务器端使用SQL Server格式比在客户端使用SQL Server格式更方便。

像上面所示的查询是非常脆弱的，因为它们将数据层与UI层紧密耦合在一起。最重要的是，这种编程风格彻底阻止了存储过程的可重用性。

我最担心的是450列的访问表，这些表是由总经理最好的朋友狗美容师的8岁儿子整理的，还有那个不可靠的查找表，它之所以存在，是因为有人不知道如何正确地规范化数据结构。

通常，这个查找表是这样的:

ID INT,
Name NVARCHAR(132),
IntValue1 INT,
IntValue2 INT,
CharValue1 NVARCHAR(255),
CharValue2 NVARCHAR(255),
Date1 DATETIME,
Date2 DATETIME

我已经记不清有多少客户的系统依赖于这种可恶的东西了。