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[数据库]sql server解析json函数


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*/ )ASBEGIN 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));    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)     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)--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+' ')     +1    SELECT    @start=PATINDEX('%[^A-Za-z0-9@+.e][A-Za-z0-9@+.e]%', ' '+@contents)   --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 ENDINSERT INTO @hierarchy (NAME, SequenceNo, parent_ID, StringValue, Object_ID, ValueType) SELECT '-',1, NULL, '', @parent_id-1, @type--  RETURNEND