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Vertica native format

Hi!

I write a dump application fo Vertica via ODBC and I almost finished with functionality - "dump to Vertica's NATIVE format", but some things are not clear for me(or missing) to finish it.


Lets talk about Vertica's example: http://my.vertica.com/docs/7.1.x/HTML/index.htm#Authoring/AdministratorsGuide/BinaryFilesAppendix/Cr...

1. How to calculate buffer length of NUMERIC field?
Formula with operators that I don't understand - "¸" and "'".
From my understanding a formula is:
CEIL((precision / 19) + 1) * 8)
2. How to convert NUMERIC field to binary format? (no description)


3. Description for BINARY column isn't clear. Why 3 bytes for BINCOL while its defined as BINARY(1)?


4. Formula for NULL values isn't clear. Can someone to elaborate it?
A series of bytes whose bits indicate whether a column contains a NULL. The most significant bit of the first byte indicates whether the first column in this row contains a NULL, the next most significant bit indicates whether the next column contains a NULL, and so on. If a bit is 1 (true) then the column contains a NULL, and there is no value for the column in the data for the row.
For example if I have 5 columns and col 3 and 5 is NULLs so indicator will be:
"00101" = False, False, True, False, True => \x05\x00
Do I understand it right?


Thanks.

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