SPSS® 12.0 Command Syntax Reference

ADD FILES 81
Variable Names. You can rename variables in each input file before combining the files using
the RENAME subcommand. This permits you to combine variables that are the same but
whose names differ in different input files, or to separate variables that are different but have
the same name.
Variable Flag. You can create a variable that indicates whether a case came from a particular
input file using IN. When interleaving cases, you can use the FIRST or LAST subcommands
to create a variable that flags the first or last case of a group of cases with the same value for
the key variable.
Variable Map. You can request a map showing all variables in the new working file, their
order, and the input files from which they came using the MAP subcommand.
Basic Specification
• The basic specification is two or more FILE subcommands, each of which specifies a file
to be combined. If cases are to be interleaved, the BY subcommand specifying the key
variables is also required.
• All variables from all input files are included in the new working file unless DROP or
KEEP is specified.
Subcommand Order
• RENAME and IN must immediately follow the FILE subcommand to which they apply.
• BY, FIRST, and LAST must follow all FILE subcommands and their associated RENAME
and IN subcommands.
Syntax Rules
• RENAME can be repeated after each FILE subcommand. RENAME applies only to variables
in the file named on the FILE subcommand immediately preceding it.
• BY can be specified only once. However, multiple key variables can be specified on BY.
When BY is used, all files must be sorted in ascending order by the key variables (see
SORT CASES).
• FIRST and LAST can be used only when files are interleaved (when BY is used).
• MAP can be repeated as often as desired.
Operations
• ADD FILES reads all input files named on FILE and builds a new working data file that replaces
any working file created earlier in the session. ADD FILES is executed when the
data are read by one of the procedure commands or the EXECUTE, SAVE, or SORT CASES
commands.