Return records from Table that are with in last 24Hours - SQL Server + ASP.NET 2.0

Hi

Have written a C# method to get data from SQL Server Database and insert into two Tables in Oracle DB.

Like to know the syntax T-SQL to use in WHERE Clause of SQL statement.

something like below: 

WHERE DATEDIFF(24hrs, getdata(), getdate() - 24)

Your help is appreciated.
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