how to write number to word function in sql server [closed]

How would one write a function in SQL Server to output a number in words?

input: 1
output: one

input: 129
output: one hundred twenty-nine


Consider using an auxiliary numbers table.

NB: This MS SQL

Create a Sequence table - This could include all the numbers you need or at least up to 999. I have limited it to the least but it adds extra logic.

CREATE TABLE [dbo].[Sequence]
    (
      seq INTEGER NOT NULL UNIQUE,
      word [varchar](25) NOT NULL
    )

INSERT INTO [Sequence] SELECT 0, ''
INSERT INTO [Sequence] SELECT 1, 'One'
INSERT INTO [Sequence] SELECT 2, 'Two'
INSERT INTO [Sequence] SELECT 3, 'Three'
INSERT INTO [Sequence] SELECT 4, 'Four'
INSERT INTO [Sequence] SELECT 5, 'Five'
INSERT INTO [Sequence] SELECT 6, 'Six'
INSERT INTO [Sequence] SELECT 7, 'Seven'
INSERT INTO [Sequence] SELECT 8, 'Eight'
INSERT INTO [Sequence] SELECT 9, 'Nine'

INSERT INTO [Sequence] SELECT 10, 'Ten'
INSERT INTO [Sequence] SELECT 11, 'Eleven'
INSERT INTO [Sequence] SELECT 12, 'Twelve'
INSERT INTO [Sequence] SELECT 13, 'Thirteen'
INSERT INTO [Sequence] SELECT 14, 'Fourteen'
INSERT INTO [Sequence] SELECT 15, 'Fifteen'
INSERT INTO [Sequence] SELECT 16, 'Sixteen'
INSERT INTO [Sequence] SELECT 17, 'Seventeen'
INSERT INTO [Sequence] SELECT 18, 'Eighteen'
INSERT INTO [Sequence] SELECT 19, 'Nineteen'

INSERT INTO [Sequence] SELECT 20, 'Twenty'
INSERT INTO [Sequence] SELECT 30, 'Thirty'
INSERT INTO [Sequence] SELECT 40, 'Forty'
INSERT INTO [Sequence] SELECT 50, 'Fifty'
INSERT INTO [Sequence] SELECT 60, 'Sixty'
INSERT INTO [Sequence] SELECT 70, 'Seventy'
INSERT INTO [Sequence] SELECT 80, 'Eighty'
INSERT INTO [Sequence] SELECT 90, 'Ninty'

Then Create the user defined function.

CREATE FUNCTION dbo.udf_NumToWords ( 
                @num AS INTEGER 
)       RETURNS VARCHAR(50)
AS
BEGIN

DECLARE @words AS VARCHAR(50)

IF      @num =     0 SELECT @words = 'Zero'
ELSE IF @num <    20 SELECT @words = word FROM sequence WHERE seq = @num
ELSE IF @num <   100 (SELECT @words = TTens.word + ' ' + TUnits.word 
                      FROM Sequence AS TUnits
                     CROSS JOIN Sequence AS TTens
                     WHERE TUnits.seq = (@num % 100) % 10
                       AND TTens.seq = (@num % 100) - (@num % 100) % 10 
                    )
ELSE IF @num =   100 (SELECT @words = THundreds.word + ' Hundred'
                      FROM Sequence AS THundreds
                     WHERE THundreds.seq = (@num / 100)
                    )
ELSE IF @num <  1000 (
                    SELECT @words = THundreds.word + ' Hundred and ' 
                                    + TTens.word + ' ' + TUnits.word 
                      FROM Sequence AS TUnits
                     CROSS JOIN Sequence AS TTens
                     CROSS JOIN Sequence AS THundreds
                     WHERE TUnits.seq = (@num % 100) % 10
                       AND TTens.seq = (@num % 100) - (@num % 100) % 10 
                       AND THundreds.seq = (@num / 100)
                    )
ELSE IF @num =  1000 (SELECT @words = TThousand.word + ' Thousand'
                      FROM Sequence AS TThousand
                     WHERE TThousand.seq = (@num / 1000)
                    )
ELSE IF @num < 10000 (
                    SELECT @words = TThousand.word + ' Thousand ' 
                                    + THundreds.word + ' Hundred and ' 
                                    + TTens.word + ' ' + TUnits.word 
                      FROM Sequence AS TUnits
                     CROSS JOIN Sequence AS TTens
                     CROSS JOIN Sequence AS THundreds
                     CROSS JOIN Sequence AS TThousand
                     WHERE TUnits.seq = (@num % 100) % 10
                       AND TTens.seq = (@num % 100) - (@num % 100) % 10 
                       AND THundreds.seq = (@num / 100) - (@num / 1000) * 10
                       AND TThousand.seq = (@num / 1000)
                    )
ELSE SELECT @words = STR(@num)

RETURN @words

END

Now Test Function:

SELECT NumberAsWords = dbo.udf_NumToWords(888);

This is slight modification of above answer by Andrew (all credits to Andrew) but this will return results in sql query without using any function

    WITH Sequence
AS (
    SELECT 0 seq
        ,'' word

    UNION ALL

    SELECT 1
        ,'One'

    UNION ALL

    SELECT 2
        ,'Two'

    UNION ALL

    SELECT 3
        ,'Three'

    UNION ALL

    SELECT 4
        ,'Four'

    UNION ALL

    SELECT 5
        ,'Five'

    UNION ALL

    SELECT 6
        ,'Six'

    UNION ALL

    SELECT 7
        ,'Seven'

    UNION ALL

    SELECT 8
        ,'Eight'

    UNION ALL

    SELECT 9
        ,'Nine'

    UNION ALL

    SELECT 10
        ,'Ten'

    UNION ALL

    SELECT 11
        ,'Eleven'

    UNION ALL

    SELECT 12
        ,'Twelve'

    UNION ALL

    SELECT 13
        ,'Thirteen'

    UNION ALL

    SELECT 14
        ,'Fourteen'

    UNION ALL

    SELECT 15
        ,'Fifteen'

    UNION ALL

    SELECT 16
        ,'Sixteen'

    UNION ALL

    SELECT 17
        ,'Seventeen'

    UNION ALL

    SELECT 18
        ,'Eighteen'

    UNION ALL

    SELECT 19
        ,'Nineteen'

    UNION ALL

    SELECT 20
        ,'Twenty'

    UNION ALL

    SELECT 30
        ,'Thirty'

    UNION ALL

    SELECT 40
        ,'Forty'

    UNION ALL

    SELECT 50
        ,'Fifty'

    UNION ALL

    SELECT 60
        ,'Sixty'

    UNION ALL

    SELECT 70
        ,'Seventy'

    UNION ALL

    SELECT 80
        ,'Eighty'

    UNION ALL

    SELECT 90
        ,'Ninty'
    )
    ,CTENumbers
AS (
    SELECT 0 AS num  --changezero to your starting number

    UNION ALL

    SELECT num + 1  
    FROM CTENumbers
    WHERE num + 1 <= 255 --change 255 to upper limit
    )
SELECT *
    ,CASE 
        WHEN num = 0
            THEN 'Zero'
        WHEN num < 20
            THEN (
                    SELECT word
                    FROM sequence
                    WHERE seq = num
                    )
        WHEN num < 100
            THEN (
                    SELECT TTens.word + ' ' + TUnits.word
                    FROM Sequence AS TUnits
                    CROSS JOIN Sequence AS TTens
                    WHERE TUnits.seq = (num % 100) % 10
                        AND TTens.seq = (num % 100) - (num % 100) % 10
                    )
        WHEN num < 1000
            THEN (
                    SELECT THundreds.word + ' Hundred and ' + TTens.word + ' ' + TUnits.word
                    FROM Sequence AS TUnits
                    CROSS JOIN Sequence AS TTens
                    CROSS JOIN Sequence AS THundreds
                    WHERE TUnits.seq = (num % 100) % 10
                        AND TTens.seq = (num % 100) - (num % 100) % 10
                        AND THundreds.seq = (num / 100)
                    )
        WHEN num = 1000
            THEN (
                    SELECT TThousand.word + ' Thousand'
                    FROM Sequence AS TThousand
                    WHERE TThousand.seq = (num / 1000)
                    )
        WHEN num < 10000
            THEN (
                    SELECT TThousand.word + ' Thousand ' + THundreds.word + ' Hundred and ' + TTens.word + ' ' + TUnits.word
                    FROM Sequence AS TUnits
                    CROSS JOIN Sequence AS TTens
                    CROSS JOIN Sequence AS THundreds
                    CROSS JOIN Sequence AS TThousand
                    WHERE TUnits.seq = (num % 100) % 10
                        AND TTens.seq = (num % 100) - (num % 100) % 10
                        AND THundreds.seq = (num / 100) - (num / 1000) * 10
                        AND TThousand.seq = (num / 1000)
                    )
        ELSE STR(num)
        END Number
FROM CTENumbers
OPTION (MAXRECURSION 10000)