SQL Server

Compress Bytes to Base64 (or any other encoding)

See more Compression Examples

Compresses bytes to base64 or any other encoding. Also decompress to return the original. SQL Server

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

    -- This example assumes the Chilkat API to have been previously unlocked.
    -- See Global Unlock Sample for sample code.

    -- First create some binary data to compress.
    DECLARE @binData int
    EXEC @hr = sp_OACreate 'Chilkat.BinData', @binData OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @i int

    SELECT @i = 1
    WHILE @i <= 16
      BEGIN
        EXEC sp_OAMethod @binData, 'AppendEncoded', @success OUT, '000102030405060708090A0B0C0D0E0F', 'hex'
        SELECT @i = @i + 1
      END

    DECLARE @compress int
    EXEC @hr = sp_OACreate 'Chilkat.Compression', @compress OUT

    EXEC sp_OASetProperty @compress, 'Algorithm', 'deflate'
    EXEC sp_OASetProperty @compress, 'EncodingMode', 'base64'

    EXEC sp_OAMethod @binData, 'GetBinary', @uncompressedBytes OUT

    -- Compress and return the compressed bytes in base64 format.
    DECLARE @compressedBase64 nvarchar(4000)
    EXEC sp_OAMethod @compress, 'CompressBytesENC', @compressedBase64 OUT, @uncompressedBytes

    PRINT 'compressed and base64 encoded: ' + @compressedBase64

    -- Compress and return in hex format:
    EXEC sp_OASetProperty @compress, 'EncodingMode', 'hex'
    DECLARE @compressedHex nvarchar(4000)
    EXEC sp_OAMethod @compress, 'CompressBytesENC', @compressedHex OUT, @uncompressedBytes

    PRINT 'compressed and hex encoded: ' + @compressedHex

    -- Now decompress..
    DECLARE @binData2 int
    EXEC @hr = sp_OACreate 'Chilkat.BinData', @binData2 OUT

    -- Decompress the base64..
    EXEC sp_OASetProperty @compress, 'EncodingMode', 'base64'
    EXEC sp_OAMethod @compress, 'DecompressBytesENC', @uncompressedBytes OUT, @compressedBase64
    EXEC sp_OAMethod @binData2, 'AppendBinary', @success OUT, @uncompressedBytes
    -- Show the uncompressed bytes in hex format:
    EXEC sp_OAMethod @binData2, 'GetEncoded', @sTmp0 OUT, 'hex'
    PRINT @sTmp0

    PRINT '--'

    -- Decompress the hex..
    EXEC sp_OASetProperty @compress, 'EncodingMode', 'hex'
    EXEC sp_OAMethod @compress, 'DecompressBytesENC', @uncompressedBytes OUT, @compressedHex
    EXEC sp_OAMethod @binData2, 'Clear', @success OUT
    EXEC sp_OAMethod @binData2, 'AppendBinary', @success OUT, @uncompressedBytes
    -- Show the uncompressed bytes in hex format:
    EXEC sp_OAMethod @binData2, 'GetEncoded', @sTmp0 OUT, 'hex'
    PRINT @sTmp0

    PRINT '--'

    EXEC @hr = sp_OADestroy @binData
    EXEC @hr = sp_OADestroy @compress
    EXEC @hr = sp_OADestroy @binData2


END
GO