SQL SERVER – Question – How to Convert Hex to Decimal

In one of the recent projects, I realize the bottleneck of the query was an inline function which was converting Hex to Decimal. I optimized the inline function and reduced the query running time to one-tenth of the original running time. Later, I was eager to find out the script my blog readers might be using for hex to decimal conversion. Please leave your comments here and I will consider all the valid answers and publish with due credit to the author in one of the future posts. If the script you have posted here is not your original script, I suggest that you include the source as well.

Reference: Pinal Dave (http://blog.SQLAuthority.com)

About these ads

24 thoughts on “SQL SERVER – Question – How to Convert Hex to Decimal

  1. Here is one way to do it:

    create function fn_HexToIntnt(@str varchar(16))
    returns bigint as begin

    select @str=upper(@str)
    declare @i int, @len int, @char char(1), @output bigint
    select @len=len(@str)
    when @len>0
    then 0
    while (@i>0)
    select @char=substring(@str,@i,1), @output=@output
    when @char between ‘A’ and ‘F’
    then 55
    when @char between ‘0’ and ‘9’
    then 48 end
    return @output

  2. hmm..
    What about using built-in function Convert?

    SELECT CONVERT(INT, 0x00000100)

    I do not pretend to be the author, but i am using this for a long time

  3. I’ve lately interested in Sql Server’s CLR support so here goes.

    First I enable CLR support on Sql Server.

    EXEC sp_CONFIGURE ‘clr enabled’ , ‘1’

    Then I create a simple DLL assembly called DBClasses with a static class named StringFormatFunctions and a static method HexToInt.

    public partial class StringFormatFunctions
    [SqlFunction(IsDeterministic = true)]
    public static int HexToInt(string input)
    return int.Parse(input, System.Globalization.NumberStyles.HexNumber);

    Next I load it to Sql Server.

    FROM ‘C:\path\DBClasses.dll’

    Finally I create a little function for it.

    CREATE FUNCTION HexToInt(@input nvarchar)
    RETURNS int
    EXTERNAL NAME DBClasses.StringFormatFunctions.HexToInt

    And now I can start to use it.

    SELECT dbo.HexToInt(‘ffff’)

  4. If you are using SQL Server 2008, you can simply use the built-in function CONVERT, with the style 1:

    SELECT CONVERT(varchar(100),0x123456789abc123,1)+’?’
    SELECT CONVERT(varbinary,’0x0123456789ABC123′,1)+0x0

    Notice that on SQL Server 2005, the above queries will not yield an error, but you will get different results (the same as if we used style 0).

    Source: http://msdn.microsoft.com/en-us/library/ms187928.aspx


  5. OK, I’m going to assume that we are starting with a string holding hex digits, and we wnat to convert that into a int.

    declare @hex varchar(10);
    set @hex = ‘BD12′;

    declare @retval int;
    set @reval = — 48402 via some magic.

    Now, this being the wacky world of SQL, the best solution is gonna be something involving a set operation on tables, so let’s start with a permanaent table mapping hex digits to their values:

    CREATE TABLE [HexDigits](
    [Digit] [char](1) NOT NULL,
    [Value] [int] NOT NULL,

    INSERT INTO [HexDigits] VALUES (‘0′, 0);
    INSERT INTO [HexDigits] VALUES (‘1′, 1);
    — etc
    INSERT INTO [HexDigits] VALUES (‘E’, 14);
    INSERT INTO [HexDigits] VALUES (‘F’, 15);

    Then, given a similar (presumably temporary) table mapping digits in the string we want translated to their digit position (count from the right), such as this,

    CREATE TABLE [HexString](
    [Digit] [char](1) NOT NULL,
    [Pos] [int] NOT NULL
    INSERT INTO [HexString] VALUES (‘B’, 4);
    INSERT INTO [HexString] VALUES (‘D’, 3);
    INSERT INTO [HexString] VALUES (‘1′, 2);
    INSERT INTO [HexString] VALUES (‘2′, 1);

    Then we have the simple query

    select SUM(POWER(16,(pos-1))*Value)
    From HexString s, HexDigits d
    where s.Digit = d.Digit

    The trick here will be the convert the original string (“BD12″, in this example), into the rows if the HexString table. I don’t know of a good way to do that, but I’m sure someone knows a simple way to do that.

  6. There is no ‘hex’ data type in sql server that we would convert from or to. We have hex literal (eg. 0xFFFF) which is int data type. We can have hex digits stored as ascii characters in varchar (e.g. ‘FFFF’, bytes 70,70,70,70 ), or as binary digits in varbinary (bytes 255, 255). You did not specify which sql type did you really want to convert from. If you want to convert from hex string to integer number, here it is:

    DECLARE @hexstr VARCHAR(10); SET @hexstr = ‘ffff’
    DECLARE @rez BIGINT; SET @rez = 0
    WHILE @hexstr ”
    SET @rez = @rez * 16 + CHARINDEX(LEFT(@hexstr,1),’0123456789ABCDEF’) – 1
    SET @hexstr = SUBSTRING(@hexstr,2,100)
    PRINT @rez

    Without loop, in one SELECT statement:

    DECLARE @hexstr VARCHAR(10); SET @hexstr = ‘ffff’
    SELECT @rez = ISNULL(@rez,0) * 16 + CHARINDEX(substring(@hexstr,n.number+1,1),’0123456789ABCDEF’) – 1
    FROM MASTER..spt_values n WHERE n.TYPE=’P’ AND n.number<len(@hexstr)
    PRINT @rez

    Vedran Kesegic

  7. Hi All,

    Please answer this,

    select convert(varbinary(2),unicode(N’B’))
    declare @tmp_var varchar(10)
    SET @tmp_var = convert(varbinary(2),unicode(N’B’))
    select @tmp_var ‘tmp_var’

    Execute this query….

    When a varbinary value is assigned to a varchar type, then it shows NULL. Why???


  8. Hi,

    please run this,

    select convert(varbinary(2),unicode(N’B’))
    declare @tmp_var varchar(10)
    SET @tmp_var = sys.fn_varbintohexstr(convert(varbinary(2),unicode(N’B’)))
    select @tmp_var ‘tmp_var’



  9. A Little late to the party, however when reading books online for convert I noticed you could apply styles when converting to binary.

    — If the value is a string without the 0x
    CAST(CONVERT(VARBINARY, ‘0000ffff’, 2) AS INT),
    — or if your string has the 0x


  10. building on Ray’s contribution above, here is the generic case:

    declare @hex varchar(64) = ‘0x00FF’
    select cast( CONVERT(VARBINARY,’0x’+right(‘00000000’+replace(@hex,’x’,”),8),1) as int)

    This could easily be made into a function.

  11. hi.
    i want to convert hex to readable string how to do pls help me its very urgent.

    i have hex like “0605040B8423F0660601AE02056A00″
    want to convert in human readable string.

    pls help …..

  12. Here is another solution

    SELECT CONVERT(int, CONVERT(varbinary, ‘0xFF’, 1)) returns 255

    so replace ‘0xFF’ with any other hex value and try. Remember to always include ‘0x’ in the beginning.

  13. today your website posts have helped me lots of times to resolve problem from my manager.
    you’re the best!!
    thank you

  14. Pingback: SQL SERVER – Answer – How to Convert Hex to Decimal or INT « SQL Server Journey with SQL Authority

    ip varchar(200)

    insert into #t
    select ‘C0A8019A’
    union all
    select ‘0A0B0028′
    union all
    select ‘0A0B2531′
    union all
    select ‘0A0B62CF’
    union all
    select ‘0A0B415F’
    union all
    select ‘0A0B62CF’
    union all
    select ‘0A0B2531′
    union all
    select ‘0A0B62CF’
    union all
    select ‘0A0B2531′
    union all
    select ‘0A0B62CF’
    union all
    select ‘0A0B415F’
    union all
    select ‘0A0B81B0′

    select ip,substring(ip,1,2) A1
    ,substring(ip,len(substring(ip,1,2))+1,2) B1
    ,substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2) C1
    ,substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2) D1

    ,case when left(substring(ip,1,2),1) =’A’ Then 10 * 16
    when left(substring(ip,1,2),1) =’B’ Then 11 * 16
    when left(substring(ip,1,2),1) =’C’ Then 12 * 16
    when left(substring(ip,1,2),1) =’D’ Then 13 * 16
    when left(substring(ip,1,2),1) =’E’ Then 14 * 16
    when left(substring(ip,1,2),1) =’F’ Then 15 * 16
    ELSE left(substring(ip,1,2),1) * 16
    case when Right(substring(ip,1,2),1) =’A’ Then 10
    when Right(substring(ip,1,2),1) =’B’ Then 11
    when Right(substring(ip,1,2),1) =’C’ Then 12
    when Right(substring(ip,1,2),1) =’D’ Then 13
    when Right(substring(ip,1,2),1) =’E’ Then 14
    when Right(substring(ip,1,2),1) =’F’ Then 15
    ELSE Right(substring(ip,1,2),1)
    END AS A

    ,case when left(substring(ip,len(substring(ip,1,2))+1,2),1) =’A’ Then 10 * 16
    when left(substring(ip,len(substring(ip,1,2))+1,2),1) =’B’ Then 11 * 16
    when left(substring(ip,len(substring(ip,1,2))+1,2),1) =’C’ Then 12 * 16
    when left(substring(ip,len(substring(ip,1,2))+1,2),1) =’D’ Then 13 * 16
    when left(substring(ip,len(substring(ip,1,2))+1,2),1) =’E’ Then 14 * 16
    when left(substring(ip,len(substring(ip,1,2))+1,2),1) =’F’ Then 15 * 16
    ELSE left(substring(ip,len(substring(ip,1,2))+1,2),1) * 16
    case when Right(substring(ip,len(substring(ip,1,2))+1,2),1) =’A’ Then 10
    when Right(substring(ip,len(substring(ip,1,2))+1,2),1) =’B’ Then 11
    when Right(substring(ip,len(substring(ip,1,2))+1,2),1) =’C’ Then 12
    when Right(substring(ip,len(substring(ip,1,2))+1,2),1) =’D’ Then 13
    when Right(substring(ip,len(substring(ip,1,2))+1,2),1) =’E’ Then 14
    when Right(substring(ip,len(substring(ip,1,2))+1,2),1) =’F’ Then 15
    ELSE Right(substring(ip,len(substring(ip,1,2))+1,2),1)
    END AS B

    ,case when left(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’A’ Then 10 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’B’ Then 11 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’C’ Then 12 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’D’ Then 13 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’E’ Then 14 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’F’ Then 15 * 16
    ELSE left(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) * 16
    case when Right(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’A’ Then 10
    when Right(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’B’ Then 11
    when Right(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’C’ Then 12
    when Right(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’D’ Then 13
    when Right(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’E’ Then 14
    when Right(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1) =’F’ Then 15
    ELSE Right(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2),1)
    END AS C

    ,case when left(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’A’ Then 10 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’B’ Then 11 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’C’ Then 12 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’D’ Then 13 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’E’ Then 14 * 16
    when left(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’F’ Then 15 * 16
    ELSE left(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) * 16
    case when Right(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’A’ Then 10
    when Right(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’B’ Then 11
    when Right(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’C’ Then 12
    when Right(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’D’ Then 13
    when Right(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’E’ Then 14
    when Right(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1) =’F’ Then 15
    ELSE Right(substring(ip,len(substring(ip,len(substring(ip,len(substring(ip,1,2))+1,2))+3,2))+5,2),1)
    END AS D
    INTO #temp
    from #t

    select ip, convert(varchar,A)+’.’+ convert(varchar,B)+’.’+convert(varchar,C) +’.’+convert(varchar,D) IPAddress from #temp

  16. Hi pinal,

    please give me solution of following error

    The TCP/IP connection to the host, port 1433 has failed. Error: “Address already in use: connect. Verify the connection properties, check that an instance of SQL Server is running on the host and accepting TCP/IP connections at the port, and that no firewall is blocking TCP connections to the port.”.
    com.websym.common.exception.DBException: org.hibernate.exception.JDBCConnectionException: Cannot open connection

    Jayesh G

  17. Pingback: SQL SERVER – Weekly Series – Memory Lane – #039 | Journey to SQL Authority with Pinal Dave

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s