我真的不建议这样做，在应用程序层中有很多更好的方法可以做到这一点，但是以下内容避免了循环，并且不那么冗长比您目前的方法:

I wouldn't really advise it, there are much better ways of doing this in the application layer, but the following avoids loops, and is a lot less verbose than your current method:

CREATE PROCEDURE dbo.GetJSON @ObjectName VARCHAR(255), @registries_per_request smallint = null
AS
BEGIN
    IF OBJECT_ID(@ObjectName) IS NULL
        BEGIN
            SELECT Json = '';
            RETURN
        END;

    DECLARE @Top NVARCHAR(20) = CASE WHEN @registries_per_request IS NOT NULL 
                                    THEN 'TOP (' + CAST(@registries_per_request AS NVARCHAR) + ') ' 
                                    ELSE '' 
                                END;

    DECLARE @SQL NVARCHAR(MAX) = N'SELECT ' + @Top + '* INTO ##T ' + 
                                'FROM ' + @ObjectName;

    EXECUTE SP_EXECUTESQL @SQL;

    DECLARE @X NVARCHAR(MAX) = '[' + (SELECT * FROM ##T FOR XML PATH('')) + ']';


    SELECT  @X = REPLACE(@X, '<' + Name + '>', 
                    CASE WHEN ROW_NUMBER() OVER(ORDER BY Column_ID) = 1 THEN '{'
                         ELSE '' END + Name + ':'),
            @X = REPLACE(@X, '</' + Name + '>', ','),
            @X = REPLACE(@X, ',{', '}, {'),
            @X = REPLACE(@X, ',]', '}]')
    FROM    sys.columns
    WHERE   [Object_ID] = OBJECT_ID(@ObjectName)
    ORDER BY Column_ID;

    DROP TABLE ##T;

    SELECT  Json = @X;

END

我将您的两部分对象名称(@schema和@table)更改为仅接受完整的对象名称.

N.B. I've changed your two part object name (@schema and @table) to just accept the full object name.

SQL小提琴示例

Example on SQL Fiddle

想法是基本上使用SQL-Server中的XML扩展将表转换为XML，然后只需将开始标记替换为{ColumnName:，将结束标记替换为,.然后，它需要再进行两次替换，才能停止在每行的最后一列中添加右括号，并从JSON字符串中删除最后一个,.

The idea is to basically use the XML extension within SQL-Server to turn the table into XML, then just replace the start tags with {ColumnName: and the end tags with ,. It then requires two more replaces to stop add the closing bracket to the last column of each row, and the remove the final , from the JSON string.