SqlServer将查询结果转换为XML和JSON_Sql Server

SqlServer将查询结果转换为XML和JSON

2020-05-21 15:55ArtlessBruin Sql Server

这篇文章主要介绍了SqlServer将查询结果转换为XML和JSON的相关资料,需要的朋友可以参考下

很久之前用到的，现在整理在这，里面一些代码来源于网上，不过有些bug已被我修改了。

1.查询结果转XML

				?

									DECLARE @ParameterSQL NVARCHAR(MAX)='SELECT * FROM table';

									DECLARE @SQL NVARCHAR(MAX)

									DECLARE @XMLString VARCHAR(MAX)

									DECLARE @XML XML

									DECLARE @Paramlist NVARCHAR(1000)

									SET @Paramlist = N'@XML XML OUTPUT'

									SET @SQL = 'WITH PrepareTable (XMLString)'

									SET @SQL = @SQL + 'AS( '

									SET @SQL = @SQL + @ParameterSQL+ ' FOR XML RAW,TYPE,ELEMENTS'

									SET @SQL = @SQL + ')'

									SET @SQL = @SQL + 'SELECT @XML=[XMLString]FROM[PrepareTable]'

									EXEC sp_executesql @SQL, @Paramlist, @XML=@XML OUTPUT

									SET @XMLString=CAST(@XML AS VARCHAR(MAX))

									SELECT @XML;

									SELECT @XMLString;

其中@ParameterSQL为要查询的语句，@XMLXML格式数据，@XMLStringXML转成字符串

2.查询结果转JSON

查询结果转换成json需要经过两个步骤，首先将查询结果转成XML数据，然后通过XML数据转成json

XML转JSON的存储过程如下：

				?

									CREATE PROCEDURE [dbo].[SerializeJSON] (

									   @XML XML,

									   @json_xml NVARCHAR(MAX) OUTPUT

									  )

									AS

									BEGIN

									  DECLARE @XMLString NVARCHAR(MAX);

									  SET @XMLString = CAST(@XML AS NVARCHAR(MAX));

									  BEGIN TRY--//开始捕捉异常

									    DECLARE @JSON NVARCHAR(MAX);

									    DECLARE @Row VARCHAR(MAX);

									    DECLARE @RowStart INT;

									    DECLARE @RowEnd INT;

									    DECLARE @FieldStart INT;

									    DECLARE @FieldEnd INT;

									    DECLARE @KEY VARCHAR(MAX);

									    DECLARE @Value VARCHAR(MAX);

									    DECLARE @StartRoot VARCHAR(100);

									    SET @StartRoot = '<row>';

									    DECLARE @EndRoot VARCHAR(100);

									    SET @EndRoot = '</row>';

									    DECLARE @StartField VARCHAR(100);

									    SET @StartField = '<';

									    DECLARE @EndField VARCHAR(100);

									    SET @EndField = '>';

									    SET @RowStart = CHARINDEX(@StartRoot, @XMLString, 0);

									    SET @JSON = '';

									    WHILE @RowStart>0

									    BEGIN

									      SET @RowStart = @RowStart + LEN(@StartRoot);

									      SET @RowEnd = CHARINDEX(@EndRoot, @XMLString, @RowStart);

									      SET @Row = SUBSTRING(@XMLString, @RowStart, @RowEnd - @RowStart);

									      SET @JSON = @JSON + '{';

									      --//for each row

									      SET @FieldStart = CHARINDEX(@StartField, @Row, 0);

									      WHILE @FieldStart>0

									      BEGIN

									        --//parse node key

									        SET @FieldStart = @FieldStart + LEN(@StartField);

									        SET @FieldEnd = CHARINDEX(@EndField, @Row, @FieldStart);

									        DECLARE @end INT = CHARINDEX('/>', @Row, @FieldStart);

									        IF @end<1

									          OR @end>@FieldEnd

									        BEGIN

									          SET @KEY = SUBSTRING(@Row, @FieldStart, @FieldEnd - @FieldStart);

									          SET @JSON = @JSON + '"' + @KEY + '":';

									          --//parse node value

									          SET @FieldStart = @FieldEnd + 1;

									          SET @FieldEnd = CHARINDEX('</', @Row, @FieldStart);

									          SET @Value = SUBSTRING(@Row, @FieldStart, @FieldEnd - @FieldStart);

									          SET @JSON = @JSON + '"' + @Value + '",';

									        END;

									        SET @FieldStart = @FieldStart + LEN(@StartField);

									        SET @FieldEnd = CHARINDEX(@EndField, @Row, @FieldStart);

									        SET @FieldStart = CHARINDEX(@StartField, @Row, @FieldEnd);

									      END;

									      IF LEN(@JSON)>0

									        SET @JSON = SUBSTRING(@JSON, 0, LEN(@JSON));

									      SET @JSON = @JSON + '},';

									      --// for each row

									      SET @RowStart = CHARINDEX(@StartRoot, @XMLString, @RowEnd);

									    END;

									    IF LEN(@JSON)>0

									      SET @JSON = SUBSTRING(@JSON, 0, LEN(@JSON));

									    --//SET @JSON = '[' + @JSON + ']';

									    SET @json_xml = @JSON;

									  END TRY--//结束捕捉异常

									  BEGIN CATCH--//有异常被捕获

									    SET @json_xml = @XMLString;

									  END CATCH;--//结束异常处理

									END;