纯SQL在SQLSERVER下执行查询表到Json的导出

1、先写个存储过程：

CREATE PROCEDURE [dbo].[SerializeJSON](
@ParameterSQL AS VARCHAR(MAX)
)
AS
BEGIN
  
DECLARE @SQL NVARCHAR(MAX)
DECLARE @XMLString NVARCHAR(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 nvarchar(MAX))
  
DECLARE @JSON nVARCHAR(MAX)
DECLARE @Row NVARCHAR(MAX)
DECLARE @RowStart INT
DECLARE @RowEnd INT
DECLARE @FieldStart INT
DECLARE @FieldEnd INT
DECLARE @KEY NVARCHAR(MAX)
DECLARE @Value NVARCHAR(MAX)
  
DECLARE @StartRoot NVARCHAR(100);SET @StartRoot='<row>'
DECLARE @EndRoot NVARCHAR(100);SET @EndRoot='</row>'
DECLARE @StartField NVARCHAR(100);SET @StartField='<'
DECLARE @EndField NVARCHAR(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)
        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+'",'
  
        SET @FieldStart=@FieldStart+Len(@StartField)
        SET @FieldEnd=CharIndex(@EndField,@Row,@FieldStart)
        SET @FieldStart=CharIndex(@StartField,@Row,@FieldEnd)
    END   
    IF LEN(@JSON)>0SET @JSON=SubString(@JSON,0,LEN(@JSON))
    SET @JSON=@JSON+'},'
    --/ for each row
  
    SET @RowStart=CharIndex(@StartRoot,@XMLString,@RowEnd)
END
IF LEN(@JSON)>0SET @JSON=SubString(@JSON,0,LEN(@JSON))
SET @JSON='['+@JSON+']'
SELECT @JSON
  
END
GO
　　

2、然后执行



EXEC sp_configure 'show advanced options', 1
GO 
RECONFIGURE
GO 
EXEC sp_configure 'xp_cmdshell', 1
GO 
RECONFIGURE
GO

EXEC xp_cmdshell 'bcp "EXEC [Xxx.Module].dbo.SerializeJSON ''SELECT * FROM SysParameter''" queryout D:data.json -c -q -T -k' --执行存储过程必须是完整的连接，否则会提示找不到存储过程

EXEC sp_configure 'show advanced options', 1
GO 
RECONFIGURE
GO 
EXEC sp_configure 'xp_cmdshell', 0
GO 
RECONFIGURE
GO




注：SQLSERVER2016及以上版本可以使用SELECT * FROM SysParameter FOR JSON PATH来生成Json数据