As explained at the question to which snailboat links, English does not employ the abbreviation resp., and it does not use the term respectively this way.
In any case, this is an awkward way to express your thought in any language. It seems more efficient (particularly to programmers, who tend to actually think this way!); but the efficiency is illusory. All you save is words; and you do this at the cost of requiring your reader to constantly stop, back up, and reframe what is being said, which ends up very confusing. You will do much better to write it a little longer, something like this (I have interpreted the Tables as external to the object or group rather than properties of the table or group; if that is an error, it will be easy to correct it):
If, after the data record has been processed, the user finds that the value in Table 1∗, Column 3 is not Null, it means that the previous value of the object to which the table refers has already been inserted. Likewise, if the value in Table 2, Column 2 is not Null, it means that the previous value of the group to which the table refers has already been inserted.
Or even simpler—that if the user finds is really superfluous:
After processing, a non-Null value in Table 1, Column 3 means that the previous value of the object to which the table refers has already been inserted. Likewise, a non-Null value in Table 2, Column 2 means that the previous value of the group to which the table refers has already been inserted.
Describe a relatively simple first instance, and use that description as a ‘template’ for describing the second instance, employing exactly the same words and highlighting the few points in which the two differ.
∗ I advise you not to use ‘First Table’ and ‘Second Table’, unless these are the actual variable names; they have a disconcertingly pompous sound, like “First Lord of the Admiralty” or “Second Book of Kings”
