It depends on what you mean by 'the database' and what workflow is best for the data you are handling, But, if you have data in a JMP table you can do this kind of thing:
NamesDefaultToHere(1);
// Make some 'date' data to play with
JMPstartDate = DateDMY(01,1,2013);
JMPendDate = Today();
dt = NewTable("DateTimes",
NewColumn("Date", Numeric, Continuous,
Formula(RandomInteger(JMPstartDate, JMPendDate)),
Format( "ddMonyyyy h:m:s", 22, 0 )
),
AddRows(1000)
);
dt << runFormulas;
Column(dt, "Date") << deleteFormula;
dt << sort(By(:Date), replaceTable);
// Exclude and hide all rows older than six months ago:
// Look for 'DateIncrement()' in 'Help > scripting Guide'.
cutoff = Date Increment( Today(), "Month", -6, "actual" );
dt << selectWhere(:Date < cutoff);
dt << hideAndExclude;
dt << clearSelect;
