Hint:
On a UNIX operating system, use gunzip to decompress the files: dbSNP_main_table and dbSNP_main_index_constraint.
The files on the SNP FTP site are UNIX files. UNIX, MS-DOS, and Macintosh text files use different characters to indicate a new line. Load the appropriate new line conversion program for your system before using bcp.

From: The Database of Short Genetic Variation (dbSNP)

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The NCBI Handbook [Internet]. 2nd edition.
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