If your data is sorted by id then one way:
data table_2;
set table_1;
by id;
if first.id;
run;
When the data step uses a BY statement each variable on the statement gets two automatic temporary variables that have values 1 (true) and 0 (false) to indicate if the current observation is the First or Last of the by group. You access those with the First.variablename or Last.variablename construct.
The IF is a subsetting if and only keeps records for the output data set where the condition is true, i.e. the first record with that value of Id.