use strict;
use warnings;

my ($start, $keyword, $end) = ('PROC SQL', 'DELQ_STATUS', 'QUIT');
my  @block;

while (<DATA>)
{
    if (/$start/i .. /$end/i)
    {
        push @block, $_;
    }

    if (/$end/i)
    {
        for (@block)
        {
            if (/AS \s+ $keyword/ix)
            {
                print join('', @block);
                last;
            }
        }

        @block = ();
    }
}

__DATA__
...

##</code><code>##

16:19 >perl 1275_SoPW.pl
481        proc sql;
482           create table work.INPUT_ACCT_POOL_3 as
483              select
484                 Acct_Key,
485                 Arrears_Bal_Amt,
486                 ARREARS_DAYS,
531                    end) as DELQ_STATUS length = 8
532                    format = 8.
533                    informat = 8.
534                    label = 'DELQ_STATUS',
535                 Arrears_Start_Date,
536                 PERIODENDING,
537                 PRODUCT_TYPE_CODE
538           from &SYSLAST
SYMBOLGEN:  Macro variable SYSLAST resolves to WORK.INPUT_ACCT_POOL_2

539           ;
NOTE: A CASE expression has no ELSE clause. Cases not accounted for by the WHEN clauses will result in a missing value for the CASE expression.
NOTE: Compressing data set WORK.INPUT_ACCT_POOL_3 decreased size by 35.05 percent.
      Compressed is 9043 pages; un-compressed would require 13923 pages.
NOTE: Table WORK.INPUT_ACCT_POOL_3 created, with 5986698 rows and 17 columns.

540        quit;

16:19 >