(SQL Server) Process Large POP3 Mailbox

Demonstrates how to read email from a mailbox that may contain a large number of emails.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @iTmp0 int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    -- This example requires the Chilkat API to have been previously unlocked.
    -- See Global Unlock Sample for sample code.

    DECLARE @mailman int
    -- Use "Chilkat_9_5_0.MailMan" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.MailMan', @mailman OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    EXEC sp_OASetProperty @mailman, 'MailHost', 'pop.example.com'

    EXEC sp_OASetProperty @mailman, 'PopUsername', 'myLogin'
    EXEC sp_OASetProperty @mailman, 'PopPassword', 'myPassword'

    EXEC sp_OASetProperty @mailman, 'MailPort', 995
    EXEC sp_OASetProperty @mailman, 'PopSsl', 1

    -- Get the list of UIDLs for all emails in the mailbox.
    DECLARE @sa int
    EXEC sp_OAMethod @mailman, 'GetUidls', @sa OUT
    EXEC sp_OAGetProperty @mailman, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 = 0
      BEGIN
        EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @mailman
        RETURN
      END

    DECLARE @i int

    DECLARE @numEmails int
    EXEC sp_OAGetProperty @sa, 'Count', @numEmails OUT
    IF @numEmails = 0
      BEGIN

        PRINT 'Mailbox is empty'
        EXEC @hr = sp_OADestroy @mailman
        RETURN
      END

    DECLARE @chunkSize int
    SELECT @chunkSize = 6

    -- Download the emails in chunks of 6 emails each.
    DECLARE @chunkBeginIdx int
    SELECT @chunkBeginIdx = 0
    DECLARE @chunkEndIdx int
    SELECT @chunkEndIdx = @chunkSize - 1
    IF @chunkEndIdx >= @numEmails
      BEGIN
        SELECT @chunkEndIdx = @numEmails - 1
      END

    DECLARE @saChunk int
    -- Use "Chilkat_9_5_0.StringArray" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.StringArray', @saChunk OUT

    WHILE (@chunkBeginIdx < @numEmails)
      BEGIN



        PRINT @chunkBeginIdx + ' to ' + @chunkEndIdx

        -- Build a chunk of UIDLs.
        EXEC sp_OAMethod @saChunk, 'Clear', NULL
        SELECT @i = @chunkBeginIdx
        WHILE @i <= @chunkEndIdx
          BEGIN
            DECLARE @success int
            EXEC sp_OAMethod @sa, 'GetString', @sTmp0 OUT, @i
            EXEC sp_OAMethod @saChunk, 'Append', @success OUT, @sTmp0
            SELECT @i = @i + 1
          END

        -- Log the UIDLs in this chunk...
        DECLARE @chunkStr nvarchar(4000)
        EXEC sp_OAMethod @saChunk, 'SaveToText', @chunkStr OUT

        PRINT @chunkStr

        -- Download this chunk of email from the POP3 server.
        DECLARE @bundle int
        EXEC sp_OAMethod @mailman, 'FetchMultiple', @bundle OUT, @saChunk
        EXEC sp_OAGetProperty @mailman, 'LastMethodSuccess', @iTmp0 OUT
        IF @iTmp0 = 0
          BEGIN
            EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
            PRINT @sTmp0
            EXEC @hr = sp_OADestroy @mailman
            EXEC @hr = sp_OADestroy @saChunk
            RETURN
          END


        EXEC sp_OAGetProperty @bundle, 'MessageCount', @iTmp0 OUT

        PRINT 'Downloaded ' + @iTmp0 + ' emails.'

        PRINT '----'

        -- Process the bundle...
        -- (your application's processing code goes here...)

        EXEC @hr = sp_OADestroy @bundle

        -- Get the next chunk...
        SELECT @chunkBeginIdx = @chunkBeginIdx + @chunkSize
        SELECT @chunkEndIdx = @chunkEndIdx + @chunkSize
        IF @chunkEndIdx >= @numEmails
          BEGIN
            SELECT @chunkEndIdx = @numEmails - 1
          END

      END

    EXEC @hr = sp_OADestroy @sa


    EXEC @hr = sp_OADestroy @mailman
    EXEC @hr = sp_OADestroy @saChunk


END
GO