I. Text Summary To go to the page where a task, programming feature, or concept was presented, select a link.

Record Formats A record format specifies the characteristics of the organization of records in a file. Some operating systems have two types of record formats: fixed-length records variable-length records. External files that have fixed-length records have an end-of-record marker after a predetermined number of columns. A typical record length is 80 columns. External files that have variable-length records have an end-of-record marker after the last field. When records contain fields of varying widths or a varying number of fields, variable-length records can use space more efficiently.

Variable-Length Records That Have a Varying Field Width The length of a record may vary because the length of a specific field varies from record to record. To read a file that has a variable-length field, a DATA step should include statements to determine the total length of each record by using the LENGTH= option hold the first record by using a single trailing @ line-hold specifier create a length-variable for the variable-length field use the $VARYINGw. informat to read the values for the variable-length field.

Variable-Length Records That Have a Varying Number of Fields Records in an external file may contain a varying number of fields. The first three lines of the DATA step that are used to read a file that contains a varying number of fields are similar to those that are used to read a file that contains a variable-length field. You need to determine the total length of each record by using the LENGTH= option hold the first record by using a single trailing @ line-hold specifier create a length variable for the variable-length field The DATA step should also include statements to read the repeating blocks of data by using an iterative DO loop.

The LENGTH= Option A LENGTH= option in the INFILE statement creates a numeric variable whose value is the length of the current record. Although the LENGTH= option is specified in the INFILE statement, the variable is not assigned a value until an INPUT statement is executed, and the SAS System determines the length of the record that is being read.

The $VARYINGw. Informat The $VARYINGw. informat is a special SAS informat that enables you to read a character value that has a different length from record to record. Before you can specify the $VARYINGw. informat, you must define the value of the length-variable.

II. Syntax To go to the page where a statement or option was presented, select a link. Variable-Length Records That Have a Varying Field Width

LIBNAME libref  'SAS-data-library';

FILENAME fileref 'filename';

DATA SAS-data-set;

INFILE raw-data-file LENGTH=total-length-variable;

INPUT variable @;

variable-length-variable=total-length-variable - value;

INPUT variable                    $VARYINGw. variable-length-variable variable(s);

RUN;

Variable-Length Records That Have a Varying Number of Fields

LIBNAME libref  'SAS-data-library';

FILENAME fileref 'filename';

DATA SAS-data-set;

INFILE raw-data-file LENGTH=total-length-variable;

INPUT variable @;

DO index-variable specification;

INPUT variable(s) @;

OUTPUT;

END;

RUN;

III. Sample Programs Variable-Length Records That Have a Varying Field Width libname perm 'c:\records\phone'; filename phonedat 'c:\records\phone\new.dat'; data perm.phones; infile phonedat length=reclen; input ID 4. @; namelen=reclen-8; input Name $varying10. namelen PhoneExt; run; Variable-Length Records That Have a Varying Number of Fields libname perm 'c:\records\patient'; filename bpdat 'c:\records\patient\bp.dat'; data perm.health; infile bpdata length=reclen; input ID 4. @; do index=6 to reclen by 15; input Date : date7. BP $ @; output; end; run;