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Come posso fare AND BIT OPERATOR tra due campi varbinary in SQL

Dopo una lunga discussione ho finalmente capito quali dati di input hai. Hai un varbinary(128) che è costruito da una stringa binaria (come '1000010010101... ') che è lunga 1024 caratteri. SQL Server non fornisce una funzione pronta che esegue tale conversione. Ne ho costruito uno per permettermi di testare. La seguente funzione esegue tale conversione:

CREATE FUNCTION dbo.binStringToBinary(@inputString VARCHAR(1024)) RETURNS VARBINARY(128) AS
BEGIN
    DECLARE @inputBinary VARBINARY(128) = convert(varbinary, '', 2)
    DECLARE @octet int = 1
    DECLARE @len int
    SET @len = Len(@inputString)
    while @octet < @len
    BEGIN
        DECLARE @i int = 0
        DECLARE @Output int = 0
        WHILE(@i < 7) BEGIN
            SET @Output = @Output + POWER(CAST(SUBSTRING(@inputString, @octet + @i, 1) AS int) * 2, 7 - @i)
            SET @i = @i + 1
        END
        SET @Output = @Output + CAST(SUBSTRING(@inputString, @octet + @i, 1) AS int)
        select @inputBinary = @inputBinary + convert(varbinary(1), @Output)
        -- PRINT substring(@inputString, @octet, 8) + ' ' + STR(@Output, 3, 0) + ' ' + convert(varchar(1024), @inputBinary, 2)
        SET @octet = @octet + 8
    END
    RETURN @inputBinary
END

Ho quindi scritto una funzione che verifica un po' usando varbinary(128) come input:

CREATE FUNCTION dbo.[DoBitsMatchFromBinary](@bitToCheck INT,@inputBinary VARBINARY(1024))
RETURNS BIT
AS
BEGIN
    IF @bitToCheck < 1 OR @bitToCheck > 1024
        RETURN 0

    DECLARE @byte int = (@bitToCheck - 1) / 8
    DECLARE @bit int = @bitToCheck - @byte * 8
    DECLARE @bytemask int = POWER(2, [email protected])
    SET @byte = @byte + 1

    RETURN CASE WHEN CONVERT(int, CONVERT(binary(1), SUBSTRING(@inputBinary, @byte, 1), 2)) & @bytemask = @bytemask THEN 1 ELSE 0 END
END

Come bonus, ho anche incluso qui una funzione che esegue il controllo dei bit da una stringa binaria di input (1024):

CREATE FUNCTION dbo.[DoBitsMatchFromBinString](@bitToCheck INT,@inputString VARCHAR(1024))
RETURNS BIT
AS
BEGIN
    IF @bitToCheck < 1 OR @bitToCheck > 1024
        RETURN 0

    RETURN CASE WHEN SUBSTRING(@inputString, @bitToCheck, 1) = '1' THEN 1 ELSE 0 END
END

Controlla il fiddle SQL che ne dimostri l'utilizzo.

DECLARE @inputBinary VARBINARY(128)
select @inputBinary = dbo.binStringToBinary('1010001000101111010111010100001101000100010111101011101010000101101000100010111101011101010000110100010001011110101110101000010110100010001011110101110101000011010001000101111010111010100001011010001000101111010111010100001101000100010111101011101010000101101000100010111101011101010000110100010001011110101110101000010110100010001011110101110101000011010001000101111010111010100001011010001000101111010111010100001101000100010111101011101010000101101000100010111101011101010000110100010001011110101110101000010110100010001011110101110101000011010001000101111010111010100001011010001000101111010111010100001101000100010111101011101010000101101000100010111101011101010000110100010001011110101110101000010110100010001011110101110101000011010001000101111010111010100001011010001000101111010111010100001101000100010111101011101010000101101000100010111101011101010000110100010001011110101110101000010110100010001011110101110101000011010001000101111010111010100001011010001000101111010111010100001101000100010111101011101010000101')
select dbo.[DoBitsMatchFromBinary](1, @inputBinary) bit1,
       dbo.[DoBitsMatchFromBinary](2, @inputBinary) bit2,
       dbo.[DoBitsMatchFromBinary](3, @inputBinary) bit3,
       dbo.[DoBitsMatchFromBinary](4, @inputBinary) bit4,
       dbo.[DoBitsMatchFromBinary](5, @inputBinary) bit5,
       dbo.[DoBitsMatchFromBinary](6, @inputBinary) bit6,
       dbo.[DoBitsMatchFromBinary](7, @inputBinary) bit7,
       dbo.[DoBitsMatchFromBinary](8, @inputBinary) bit8,
       dbo.[DoBitsMatchFromBinary](1017, @inputBinary) bit1017,
       dbo.[DoBitsMatchFromBinary](1018, @inputBinary) bit1018,
       dbo.[DoBitsMatchFromBinary](1019, @inputBinary) bit1019,
       dbo.[DoBitsMatchFromBinary](1020, @inputBinary) bit1020,
       dbo.[DoBitsMatchFromBinary](1021, @inputBinary) bit1021,
       dbo.[DoBitsMatchFromBinary](1022, @inputBinary) bit1022,
       dbo.[DoBitsMatchFromBinary](1023, @inputBinary) bit1023,
       dbo.[DoBitsMatchFromBinary](1024, @inputBinary) bit1024


| bit1 |  bit2 | bit3 |  bit4 |  bit5 |  bit6 | bit7 |  bit8 | bit1017 | bit1018 | bit1019 | bit1020 | bit1021 | bit1022 | bit1023 | bit1024 |
|------|-------|------|-------|-------|-------|------|-------|---------|---------|---------|---------|---------|---------|---------|---------|
| true | false | true | false | false | false | true | false |    true |   false |   false |   false |   false |    true |   false |    true |