Keep the obs based on Date

[sas_]

Hi i am having main table the incre table append to the main table
but while appending to the Main table based on pid and dt it should remove the older one
ex in main table pid a1 is there again in incr table again pid with a1 came but with diff no
so it should append to main table and remove the older one based on date

Main Table

Pid no Dt
a1  1  12jan2011
a2  2  12jan2011
a3  3  12jan2011

Incre Table
Pid no Dt
a1  5  18jan2011
a4  6  18jan2011
a5  7  18jan2011

Output
Pid no Dt
a1  5  18jan2011
a2  2  12jan2011
a3  3  12jan2011
a4  6  18jan2011
a5  7  18jan2011

[art297]

If your data are already sorted by pid, then you could just use:

data Main;

  informat dt date9.;

  input Pid $ no Dt;

  cards;

a1  1  12jan2011

a2  2  12jan2011

a3  3  12jan2011

;

data Incre;

  informat dt date9.;

  input Pid $ no Dt;

  cards;

a1  5  18jan2011

a4  6  18jan2011

a5  7  18jan2011

;

data Output;

  format dt date9.;

  update main incre;

  by pid;

run;