As SAS processes a larger
subset of the data, more CPU resources are required. However, positioning
of the subsetting IF statement in a DATA step can affect performance
and efficiency.
Correct answer: c
The DATA step is the
only technique that can be used to modify both data values and variable
attributes. The DATASETS procedure enables you to modify only variable
attributes.
Correct answer: d
For selecting observations,
a WHERE statement is more efficient than a subsetting IF statement
because it examines what is in the input page buffer and selects observations
before they are loaded into the program data vector, which results
in a savings in CPU operations.
Correct answer: a
It is more advantageous
to create a temporary SAS data set rather than a permanent SAS data
set when the external file on which the data set is based is frequently
updated between SAS sessions.
Correct answer: c
A one-step DATASETS
procedure results in a savings of CPU usage and I/O operations. PROC
DATASETS supports RUN-group processing, which enables you to process
multiple SAS data sets from the same library with one invocation of
the procedure.
