Language Reference

DELETE Statement

marks observations for deletion

DELETE <range> <WHERE(expression)>;

The inputs to the DELETE statement are as follows:

range

specifies a range of observations.

expression

is an expression that is evaluated for being true or false.

Use the DELETE statement to mark records for deletion in the current output data set. To delete records and renumber the remaining observations, use the PURGE statement.

You can specify range by using a keyword or by record number using the POINT operand. The following keywords are valid values for range:

ALL

specifies all observations.

CURRENT

specifies the current observation.

NEXT <number>

specifies the next observation or the next number of observations.

AFTER

specifies all observations after the current one.

POINT operand

specifies observations by number, where operand is one of the following:

Operand	Example
a single record number	point 5
a literal giving several	point {2 5 10}
record numbers
the name of a matrix	point p
containing record numbers
an expression in parentheses	point (p+1)

CURRENT is the default value for range. If the current data set has an index in use, the POINT option is invalid.

The WHERE clause conditionally selects observations that are contained within the range specification. The general form of the WHERE clause is

WHERE( variable comparison-op operand)

In the preceding statement,

variable

is a variable in the SAS data set.

comparison-op

is one of the following comparison operators:

<

less than

<=

less than or equal to

=

equal to

>

greater than

>=

greater than or equal to

^=

not equal to

?

contains a given string

^?

does not contain a given string

= :

begins with a given string

= *

sounds like or is spelled like a given string

operand

is a literal value, a matrix name, or an expression in parentheses.

WHERE comparison arguments can be matrices. For the following operators, the WHERE clause succeeds if all the elements in the matrix satisfy the condition:

^=   ^?   <   <=   >   >=

For the following operators, the WHERE clause succeeds if any of the elements in the matrix satisfy the condition:

=   ?   = :   = *

Logical expressions can be specified within the WHERE clause by using the AND (&) and OR (|) operators. The general form is as follows:

	clause&clause		(for an AND clause)
	clause|clause		(for an AND clause)

where clause can be a comparison, a parenthesized clause, or a logical expression clause that is evaluated by using operator precedence.

Note: The expression on the left-hand side refers to values of the data set variables and the expression on the right-hand side refers to matrix values.

Here are several examples of DELETE statements:

  
    delete;                     /* deletes the current obs  */ 
    delete point 34;            /* deletes obs 34           */ 
    delete all where(age<21);   /* deletes obs where age<21 */
 

You can use the SETOUT statement with the DELETE statement as follows:

  
    setout class point 34;     /* makes CLASS current output */ 
    delete;                    /* deletes ob 34              */
 

Observations deleted by using the DELETE statement are not physically removed from the data set until a PURGE statement is issued.