设计用于创建Sql查询的模式-DesignPatternforCreatingSqlQueries

3  

This sort of thing is frequently done by using the Builder Pattern.

这种事情通常是通过使用Builder模式来完成的。

If you want to support very complex queries, it might be a rather complex builder, and other patterns might come into play, but this is where I would start.

如果您希望支持非常复杂的查询，那么它可能是一个相当复杂的构建器，其他模式可能会发挥作用，但我将从这里开始。

2  

I used the following design :

我采用了以下设计:

Is it a oop good design?

这是一个好的设计吗?

The little trick is to put a "WHERE 1 = 1" so you don't have to handle if ti's a AND or a WHERE you have to add.

这里有个小技巧，就是把"WHERE 1 = 1"这样你就不需要处理ti是a还是a了。

0  

this is how I do: (srp is an object that contains all the possible parameters)

我是这样做的:(srp是一个包含所有可能参数的对象)

   string query = "select * from TABLE";

        if (srp != null)
        {
            query += " Where ";
            bool firstParameter = true;

            if (srp.ID!= 0)
            {
                if (!firstParameter)
                {
                    query += " and ";
                }
                query += " ID= " + srp.ID.ToString();
                firstParameter = false;
            }
        }

then you can replicate the inner if as much as you need.

然后你可以复制内部，如果你需要的话。

Of course, this will only work with AND parameters, still didn't have to create a more complex logic to use or

当然，这只适用于和参数，仍然不需要创建更复杂的逻辑来使用or