Oracle SQL Return all records within days of date

I am hoping that somebody can help me out with this question.

The following SQL returns just the records in a given table that are specifically 20 days from current.

Last_Mod_Date = TO_DATE(SYSDATE - 20)

Using 开发者_如何学编程similar theory can somebody help me determine how to return all records within the past 20 days range?

Thanks!

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select 
  *
from
  table
where
  Last_Mod_Date >= trunc(sysdate-20);

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SELECT * 
FROM MY_TABLE 
WHERE TO_DATE(my_ts_field) BETWEEN TO_DATE(SYSDATE-20) AND TO_DATE(SYSDATE)

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Change the comparison to greater-than-or-equal:

Last_Mod_Date >= TO_DATE(SYSDATE-20)