Longtable margin

I use the package longtable for build tables. But the table has many columns, then it to fall outside the limits page. How do I fix this? And how to change the margin for tables?

Look at the example:

Thanks.

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use package ltablex or ltxtable. Documentations are available by running texdoc <package name> –  Herbert Jun 3 '12 at 8:20
Thanks @Herbert it useful for me. –  mark Jun 3 '12 at 8:55