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Can MapInfo TAB integer fields hold null values?

Is there a spec document on MapInfo TAB attributes available for download?

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up vote 5 down vote accepted

Unfortunately the tab file format doesn't support NULL values. If you need NULL values you need to define your own NULL values, for instance -9999.

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Ha-ha, you dont know how many issues this has given my clients in the past! – Hairy Jan 9 '12 at 14:27

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