SAS Chapter 21: Controlling Data Storage Space

The descriptor portion is stored on whatever page has enough room for it.

New observations are always added in the first sufficient available space.

Deleted observation space is tracked.

New observations are always added at the end of the data set.

The descriptor portion is stored on whatever data set page has enough room for it.

Deleted observation spaced can be reused.

Compressed SAS data files have a smaller overhead than uncompressed SAS data files.

In a compressed SAS data set, each observation must be the same size.

data temp; infile file1; input x 4. y 3. z 2.; run;

data temp; format x 4. y 3. z 2.; infile file1; input x 4. y 3. z 2.; run;

data temp; length x 4 y 3 z 2; infile file1; input x 4. y 3. z 2.; run;

data temp; informat x 4. y 3. z 2.; infile file1; input x 4. y 3. z 2.; run;

SAS data views use less disk space but more CPU resources than SAS data files.

SAS data views can be created only in permanent SAS data libraries.

SAS data views use less CPU resources but more disk space than SAS data files.

SAS data views can be created only in temporary SAS data libraries.

proc contents data=company.regular; compare data=company.reduced; run;

proc compare base=company.regular compare=company.reduced; run;

proc print data=company.regular; run; proc print data=company.reduced; run;

proc datasets library=company; contents data=regular compare=reduced; run;