时间：2021-07-01 10:21:17 帮助过：2人阅读
针对json解析需要一个自定义类型Hierarchy、一个表值函数parseJSON、一个标量值函数ToJSON。语句如下：
1 /****** Object: UserDefinedTableType [dbo].[Hierarchy] Script Date: 2016/5/6 17:24:48 ******/ 2 CREATE TYPE [dbo].[Hierarchy] AS TABLE( 3 [element_id] [INT] NOT NULL, 4 [sequenceNo] [INT] NULL, 5 [parent_ID] [INT] NULL, 6 [Object_ID] [INT] NULL, 7 [NAME] [NVARCHAR](2000) NULL, 8 [StringValue] [NVARCHAR](MAX) NOT NULL, 9 [ValueType] [VARCHAR](10) NOT NULL, 10 PRIMARY KEY CLUSTERED 11 ( 12 [element_id] ASC 13 )WITH (IGNORE_DUP_KEY = OFF) 14 ) 15 GOHierarchy
CREATE FUNCTION [dbo].[parseJSON]( @JSON NVARCHAR(MAX)) RETURNS @hierarchy TABLE ( element_id INT IDENTITY(1, 1) NOT NULL, /* internal surrogate primary key gives the order of parsing and the list order */ sequenceNo [int] NULL, /* the place in the sequence for the element */ parent_ID INT,/* if the element has a parent then it is in this column. The document is the ultimate parent, so you can get the structure from recursing from the document */ Object_ID INT,/* each list or object has an object id. This ties all elements to a parent. Lists are treated as objects here */ NAME NVARCHAR(2000),/* the name of the object */ StringValue NVARCHAR(MAX) NOT NULL,/*the string representation of the value of the element. */ ValueType VARCHAR(10) NOT null /* the declared type of the value represented as a string in StringValue*/ ) AS BEGIN DECLARE @FirstObject INT, --the index of the first open bracket found in the JSON string @OpenDelimiter INT,--the index of the next open bracket found in the JSON string @NextOpenDelimiter INT,--the index of subsequent open bracket found in the JSON string @NextCloseDelimiter INT,--the index of subsequent close bracket found in the JSON string @Type NVARCHAR(10),--whether it denotes an object or an array @NextCloseDelimiterChar CHAR(1),--either a ‘}‘ or a ‘]‘ @Contents NVARCHAR(MAX), --the unparsed contents of the bracketed expression @Start INT, --index of the start of the token that you are parsing @end INT,--index of the end of the token that you are parsing @param INT,--the parameter at the end of the next Object/Array token @EndOfName INT,--the index of the start of the parameter at end of Object/Array token @token NVARCHAR(200),--either a string or object @value NVARCHAR(MAX), -- the value as a string @SequenceNo int, -- the sequence number within a list @name NVARCHAR(200), --the name as a string @parent_ID INT,--the next parent ID to allocate @lenJSON INT,--the current length of the JSON String @characters NCHAR(36),--used to convert hex to decimal @result BIGINT,--the value of the hex symbol being parsed @index SMALLINT,--used for parsing the hex value @Escape INT --the index of the next escape character DECLARE @Strings TABLE /* in this temporary table we keep all strings, even the names of the elements, since they are ‘escaped‘ in a different way, and may contain, unescaped, brackets denoting objects or lists. These are replaced in the JSON string by tokens representing the string */ ( String_ID INT IDENTITY(1, 1), StringValue NVARCHAR(MAX) ) SELECT--initialise the characters to convert hex to ascii @characters=‘0123456789abcdefghijklmnopqrstuvwxyz‘, @SequenceNo=0, --set the sequence no. to something sensible. /* firstly we process all strings. This is done because [{} and ] aren‘t escaped in strings, which complicates an iterative parse. */ @parent_ID=0; WHILE 1=1 --forever until there is nothing more to do BEGIN SELECT @start=PATINDEX(‘%[^a-zA-Z]["]%‘, @json collate SQL_Latin1_General_CP850_Bin);--next delimited string IF @start=0 BREAK --no more so drop through the WHILE loop IF SUBSTRING(@json, @start+1, 1)=‘"‘ BEGIN --Delimited Name SET @start=@Start+1; SET @end=PATINDEX(‘%[^\]["]%‘, RIGHT(@json, LEN(@json+‘|‘)-@start) collate SQL_Latin1_General_CP850_Bin); END IF @end=0 --no end delimiter to last string BREAK --no more SELECT @token=SUBSTRING(@json, @start+1, @end-1) --now put in the escaped control characters SELECT @token=REPLACE(@token, FROMString, TOString) FROM (SELECT ‘\"‘ AS FromString, ‘"‘ AS ToString UNION ALL SELECT ‘\\‘, ‘\‘ UNION ALL SELECT ‘\/‘, ‘/‘ UNION ALL SELECT ‘\b‘, CHAR(08) UNION ALL SELECT ‘\f‘, CHAR(12) UNION ALL SELECT ‘\n‘, CHAR(10) UNION ALL SELECT ‘\r‘, CHAR(13) UNION ALL SELECT ‘\t‘, CHAR(09) ) substitutions SELECT @result=0, @escape=1 --Begin to take out any hex escape codes WHILE @escape>0 BEGIN SELECT @index=0, --find the next hex escape sequence @escape=PATINDEX(‘%\x[0-9a-f][0-9a-f][0-9a-f][0-9a-f]%‘, @token collate SQL_Latin1_General_CP850_Bin) IF @escape>0 --if there is one BEGIN WHILE @index<4 --there are always four digits to a \x sequence BEGIN SELECT --determine its value @result=@result+POWER(16, @index) *(CHARINDEX(SUBSTRING(@token, @escape+2+3-@index, 1), @characters)-1), @index=@index+1 ; END -- and replace the hex sequence by its unicode value SELECT @token=STUFF(@token, @escape, 6, NCHAR(@result)) END END --now store the string away INSERT INTO @Strings (StringValue) SELECT @token -- and replace the string with a token SELECT @JSON=STUFF(@json, @start, @end+1, ‘@string‘+CONVERT(NVARCHAR(5), @@identity)) END -- all strings are now removed. Now we find the first leaf. WHILE 1=1 --forever until there is nothing more to do BEGIN SELECT @parent_ID=@parent_ID+1 --find the first object or list by looking for the open bracket SELECT @FirstObject=PATINDEX(‘%[{[[]%‘, @json collate SQL_Latin1_General_CP850_Bin)--object or array IF @FirstObject = 0 BREAK IF (SUBSTRING(@json, @FirstObject, 1)=‘{‘) SELECT @NextCloseDelimiterChar=‘}‘, @type=‘object‘ ELSE SELECT @NextCloseDelimiterChar=‘]‘, @type=‘array‘ SELECT @OpenDelimiter=@firstObject WHILE 1=1 --find the innermost object or list... BEGIN SELECT @lenJSON=LEN(@JSON+‘|‘)-1 --find the matching close-delimiter proceeding after the open-delimiter SELECT @NextCloseDelimiter=CHARINDEX(@NextCloseDelimiterChar, @json, @OpenDelimiter+1) --is there an intervening open-delimiter of either type SELECT @NextOpenDelimiter=PATINDEX(‘%[{[[]%‘, RIGHT(@json, @lenJSON-@OpenDelimiter)COLLATE SQL_Latin1_General_CP850_Bin)--object IF @NextOpenDelimiter=0 BREAK SELECT @NextOpenDelimiter=@NextOpenDelimiter+@OpenDelimiter IF @NextCloseDelimiter<@NextOpenDelimiter BREAK IF SUBSTRING(@json, @NextOpenDelimiter, 1)=‘{‘ SELECT @NextCloseDelimiterChar=‘}‘, @type=‘object‘ ELSE SELECT @NextCloseDelimiterChar=‘]‘, @type=‘array‘ SELECT @OpenDelimiter=@NextOpenDelimiter END ---and parse out the list or name/value pairs SELECT @contents=SUBSTRING(@json, @OpenDelimiter+1, @NextCloseDelimiter-@OpenDelimiter-1) SELECT @JSON=STUFF(@json, @OpenDelimiter, @NextCloseDelimiter-@OpenDelimiter+1, ‘@‘+@type+CONVERT(NVARCHAR(5), @parent_ID)) WHILE (PATINDEX(‘%[A-Za-z0-9@+.e]%‘, @contents COLLATE SQL_Latin1_General_CP850_Bin))<>0 BEGIN IF @Type=‘Object‘ --it will be a 0-n list containing a string followed by a string, number,boolean, or null BEGIN SELECT @SequenceNo=0,@end=CHARINDEX(‘:‘, ‘ ‘+@contents)--if there is anything, it will be a string-based name. SELECT @start=PATINDEX(‘%[^A-Za-z@][@]%‘, ‘ ‘+@contents COLLATE SQL_Latin1_General_CP850_Bin)--AAAAAAAA SELECT @token=SUBSTRING(‘ ‘+@contents, @start+1, @End-@Start-1), @endofname=PATINDEX(‘%[0-9]%‘, @token COLLATE SQL_Latin1_General_CP850_Bin), @param=RIGHT(@token, LEN(@token)-@endofname+1) SELECT @token=LEFT(@token, @endofname-1), @Contents=RIGHT(‘ ‘+@contents, LEN(‘ ‘+@contents+‘|‘)-@end-1) SELECT @name=stringvalue FROM @strings WHERE string_id=@param --fetch the name END ELSE SELECT @Name=NULL,@SequenceNo=@SequenceNo+1 SELECT @end=CHARINDEX(‘,‘, @contents)-- a string-token, object-token, list-token, number,boolean, or null IF @end=0 SELECT @end=PATINDEX(‘%[A-Za-z0-9@+.e][^A-Za-z0-9@+.e]%‘, @Contents+‘ ‘ COLLATE SQL_Latin1_General_CP850_Bin) +1 SELECT @start=PATINDEX(‘%[^A-Za-z0-9@+.e][A-Za-z0-9@+.e]%‘, ‘ ‘+@contents COLLATE SQL_Latin1_General_CP850_Bin) --select @start,@end, LEN(@contents+‘|‘), @contents SELECT @Value=RTRIM(SUBSTRING(@contents, @start, @End-@Start)), @Contents=RIGHT(@contents+‘ ‘, LEN(@contents+‘|‘)-@end) IF SUBSTRING(@value, 1, 7)=‘@object‘ INSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, Object_ID, ValueType) SELECT @name, @SequenceNo, @parent_ID, SUBSTRING(@value, 8, 5), SUBSTRING(@value, 8, 5), ‘object‘ ELSE IF SUBSTRING(@value, 1, 6)=‘@array‘ INSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, Object_ID, ValueType) SELECT @name, @SequenceNo, @parent_ID, SUBSTRING(@value, 7, 5), SUBSTRING(@value, 7, 5), ‘array‘ ELSE IF SUBSTRING(@value, 1, 7)=‘@string‘ INSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, ValueType) SELECT @name, @SequenceNo, @parent_ID, stringvalue, ‘string‘ FROM @strings WHERE string_id=SUBSTRING(@value, 8, 5) ELSE IF @value IN (‘true‘, ‘false‘) INSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, ValueType) SELECT @name, @SequenceNo, @parent_ID, @value, ‘boolean‘ ELSE IF @value=‘null‘ INSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, ValueType) SELECT @name, @SequenceNo, @parent_ID, @value, ‘null‘ ELSE IF PATINDEX(‘%[^0-9]%‘, @value COLLATE SQL_Latin1_General_CP850_Bin)>0 INSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, ValueType) SELECT @name, @SequenceNo, @parent_ID, @value, ‘real‘ ELSE INSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, ValueType) SELECT @name, @SequenceNo, @parent_ID, @value, ‘int‘ IF @Contents=‘ ‘ SELECT @SequenceNo=0 END END INSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, Object_ID, ValueType) SELECT ‘-‘,1, NULL, ‘‘, @parent_id-1, @type -- RETURN ENDparseJSON
1 /****** Object: UserDefinedFunction [dbo].[ToJSON] Script Date: 2016/5/6 17:25:49 ******/ 2 SET ANSI_NULLS ON 3 GO 4 5 SET QUOTED_IDENTIFIER ON 6 GO 7 8 CREATE FUNCTION [dbo].[ToJSON] 9 ( 10 @Hierarchy Hierarchy READONLY 11 ) 12 13 /* 14 the function that takes a Hierarchy table and converts it to a JSON string 15 16 Author: Phil Factor 17 Revision: 1.5 18 date: 1 May 2014 19 why: Added a fix to add a name for a list. 20 example: 21 22 Declare @XMLSample XML 23 Select @XMLSample=‘ 24 <glossary><title>example glossary</title> 25 <GlossDiv><title>S</title> 26 <GlossList> 27 <GlossEntry ID="SGML" SortAs="SGML"> 28 <GlossTerm>Standard Generalized Markup Language</GlossTerm> 29 <Acronym>SGML</Acronym> 30 <Abbrev>ISO 8879:1986</Abbrev> 31 <GlossDef> 32 <para>A meta-markup language, used to create markup languages such as DocBook.</para> 33 <GlossSeeAlso OtherTerm="GML" /> 34 <GlossSeeAlso OtherTerm="XML" /> 35 </GlossDef> 36 <GlossSee OtherTerm="markup" /> 37 </GlossEntry> 38 </GlossList> 39 </GlossDiv> 40 </glossary>‘ 41 42 DECLARE @MyHierarchy Hierarchy -- to pass the hierarchy table around 43 insert into @MyHierarchy select * from dbo.ParseXML(@XMLSample) 44 SELECT dbo.ToJSON(@MyHierarchy) 45 46 */ 47 RETURNS NVARCHAR(MAX)--JSON documents are always unicode. 48 AS 49 BEGIN 50 DECLARE 51 @JSON NVARCHAR(MAX), 52 @NewJSON NVARCHAR(MAX), 53 @Where INT, 54 @ANumber INT, 55 @notNumber INT, 56 @indent INT, 57 @ii INT, 58 @CrLf CHAR(2)--just a simple utility to save typing! 59 60 --firstly get the root token into place 61 SELECT @CrLf=CHAR(13)+CHAR(10),--just CHAR(10) in UNIX 62 @JSON = CASE ValueType WHEN ‘array‘ THEN 63 +COALESCE(‘{‘+@CrLf+‘ "‘+NAME+‘" : ‘,‘‘)+‘[‘ 64 ELSE ‘{‘ END 65 +@CrLf 66 + CASE WHEN ValueType=‘array‘ AND NAME IS NOT NULL THEN ‘ ‘ ELSE ‘‘ END 67 + ‘@Object‘+CONVERT(VARCHAR(5),OBJECT_ID) 68 +@CrLf+CASE ValueType WHEN ‘array‘ THEN 69 CASE WHEN NAME IS NULL THEN ‘]‘ ELSE ‘ ]‘+@CrLf+‘}‘+@CrLf END 70 ELSE ‘}‘ END 71 FROM @Hierarchy 72 WHERE parent_id IS NULL AND valueType IN (‘object‘,‘document‘,‘array‘) --get the root element 73 /* now we simply iterat from the root token growing each branch and leaf in each iteration. This won‘t be enormously quick, but it is simple to do. All values, or name/value pairs withing a structure can be created in one SQL Statement*/ 74 SELECT @ii=1000 75 WHILE @ii>0 76 BEGIN 77 SELECT @where= PATINDEX(‘%[^[a-zA-Z0-9]@Object%‘,@json)--find NEXT token 78 IF @where=0 BREAK 79 /* this is slightly painful. we get the indent of the object we‘ve found by looking backwards up the string */ 80 SET @indent=CHARINDEX(CHAR(10)+CHAR(13),REVERSE(LEFT(@json,@where))+CHAR(10)+CHAR(13))-1 81 SET @NotNumber= PATINDEX(‘%[^0-9]%‘, RIGHT(@json,LEN(@JSON+‘|‘)-@Where-8)+‘ ‘)--find NEXT token 82 SET @NewJSON=NULL --this contains the structure in its JSON form 83 SELECT 84 @NewJSON=COALESCE(@NewJSON+‘,‘+@CrLf+SPACE(@indent),‘‘) 85 +CASE WHEN parent.ValueType=‘array‘ THEN ‘‘ ELSE COALESCE(‘"‘+TheRow.NAME+‘" : ‘,‘‘) END 86 +CASE TheRow.valuetype 87 WHEN ‘array‘ THEN ‘ [‘+@CrLf+SPACE(@indent+2) 88 +‘@Object‘+CONVERT(VARCHAR(5),TheRow.[OBJECT_ID])+@CrLf+SPACE(@indent+2)+‘]‘ 89 WHEN ‘object‘ THEN ‘ {‘+@CrLf+SPACE(@indent+2) 90 +‘@Object‘+CONVERT(VARCHAR(5),TheRow.[OBJECT_ID])+@CrLf+SPACE(@indent+2)+‘}‘ 91 WHEN ‘string‘ THEN ‘"‘+dbo.JSONEscaped(TheRow.StringValue)+‘"‘ 92 ELSE TheRow.StringValue 93 END 94 FROM @Hierarchy TheRow 95 INNER JOIN @hierarchy Parent 96 ON parent.element_ID=TheRow.parent_ID 97 WHERE TheRow.parent_id= SUBSTRING(@JSON,@where+8, @Notnumber-1) 98 /* basically, we just lookup the structure based on the ID that is appended to the @Object token. Simple eh? */ 99 --now we replace the token with the structure, maybe with more tokens in it. 100 SELECT @JSON=STUFF (@JSON, @where+1, 8+@NotNumber-1, @NewJSON),@ii=@ii-1 101 END 102 RETURN @JSON 103 END 104 105 GOtoJson
Sql Server xml 类型字段的增删改查 文章中介绍了几种用法，我这里非常简单。有一张表 Candidate_Ext，CVParseJson 字段存储了json格式数据，其中有个节点是SkillName存储了技能列表，这里使用sql语句把技能名称查出来逗号分隔。
"SkillList": [ { "SkillId": 0, "CandidateId": 0, "TenantId": 0, "SkillName": "Oracle", "SkillLevel": 0, "SkillLevelName": "熟练", "SkillLevelName1": null }, { "SkillId": 0, "CandidateId": 0, "TenantId": 0, "SkillName": "TCP/IP", "SkillLevel": 0, "SkillLevelName": "精通", "SkillLevelName1": null } ],
sql语句：
SELECT TOP 1 l.CandidateId ,l.CVParseJson, ( SELECT StringValue+‘,‘ FROM parseJSON(l.CVParseJson) json WHERE json.NAME=‘SkillName‘ FOR XML PATH(‘‘) ) 专业技能 FROM dbo.Candidate_Ext l WHERE CVParseJson LIKE ‘{"candi%‘
结果：
CandidateId 专业技能 1 Oracle,TCP/IP,
如果多个节点都有SkillName 这个属性处理起来就比较麻烦了，性能也不见得好，所以小数据出来使用这个方法还是比较方便的。
为sql server 增加 parseJSON 和 ToJSON 函数
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