SQL> set stat on; select count (*) from td;

                COUNT
=====================
             10000000

Current memory = 2450777544
Delta memory = 251512
Max memory = 2450847176
Elapsed time= 8.33 sec
Cpu = 0.00 sec
Buffers = 524288
Reads = 1431185
Writes = 0
Fetches = 22860497

строка:  'q________________________. . .________________'
шаблон: '%q%'

TD (128)
    Primary pointer page: 200, Index root page: 201
    Total formats: 1, used formats: 1
    Average record length: 528.50, total records: 10000000
    Average version length: 0.00, total versions: 0, max versions: 0
    Average fragment length: 0.00, total fragments: 0, max fragments: 0
    Average unpacked length: 32770.00, compression ratio: 62.01
    Pointer pages: 1583, data page slots:  1'428'572 
    Data pages:  1'428'572 , average fill: 94%
    Primary pages: 1428572, full pages: 1428571, swept pages: 0
    Fill distribution:
         0 - 19% = 0
        20 - 39% = 0
        40 - 59% = 1
        60 - 79% = 0
        80 - 99% = 1428571

 
 
 query [code=plaintext]SQL>     select
CON>       current_time dts
CON>       -- mon$attachments:
CON>       ,cast(row_number()over(order by mon$attachment_id) as char(3)) rn
CON>       ,a.mon$remote_address remote_IP
CON>       ,a.mon$attachment_id attach_id
CON>       ,a.mon$user mon_user
CON>       ,a.mon$stat_id       stat_id
CON>       ,a.mon$server_pid    server_PID
CON>       ,a.mon$remote_pid    remote_PID
CON>       -- mon$memory_usage:
CON>       ,u.mon$memory_used used_memory
CON>       ,u.mon$memory_allocated alloc_by_OS
CON>       -- mon$io_stats:
CON>       ,i.mon$page_reads reads
CON>       ,i.mon$page_writes writes
CON>       ,i.mon$page_fetches fetches
CON>       ,i.mon$page_marks marks
CON>       -- mon$record_stats:
CON>       ,r.mon$record_seq_reads seq_reads
CON>       ,r.mon$record_idx_reads idx_reads
CON>       ,r.mon$record_inserts ins_cnt
CON>       ,r.mon$record_updates upd_cnt
CON>       ,r.mon$record_deletes del_cnt
CON>       ,r.mon$record_backouts bk_outs
CON>       ,r.mon$record_purges purges
CON>       ,r.mon$record_expunges expunges
CON>       -- aux info:
CON>       ,right(a.mon$remote_process,30) remote_process
CON>       -- mon$statements:
CON>       --,left(cast(s.mon$sql_text as varchar(32760)),50) sql_txt
CON>     from mon$attachments a
CON>     --left join mon$statements s on a.mon$attachment_id = s.mon$attachment_id
CON>     left join mon$memory_usage u on a.mon$stat_id=u.mon$stat_id
CON>     left join mon$io_stats i on a.mon$stat_id=i.mon$stat_id
CON>     left join mon$record_stats r on a.mon$stat_id=r.mon$stat_id
CON>     where
CON>     --a.mon$state=1 and
CON>     a.mon$attachment_id<>current_connection
CON>     --order by a.mon$attachment_id
CON> ;

set term ^;
execute block returns(cnt int) as
declare n int = 10000000;
declare s varchar( 32760 );
. . .
Elapsed time=  34.18 sec 

=== vs ===

declare n int = 10000000;
declare s varchar( 50 );
. . .
Elapsed time=  6.68 sec 

import static java.lang.System.*;
import java.util.regex.*;
class MatchesCount {
  public static void main(String[] args) {
    int pad = args.length > 0 ? Integer.parseInt(args[0]) : 32760;
    String s = String.format("%1$-" + pad + "s", "q");
    //out.println("s=>"+s+"<");
    Pattern p = Pattern.compile(".*?q.*?");
    Matcher m;
    int cnt=0;
    long t0 = currentTimeMillis();
    for(int i=0; i < 10000000; i++) {
      m=p.matcher(s);
      cnt += m.find() ? 1 : 0;
    }
    out.println("s.length()="+s.length()+", cnt="+cnt+", done at "+(  currentTimeMillis() - t0 )+" ms");
  }
}

D:\JAVA>java MatchesCount 10
s.length()=10, cnt=10000000, done at 5562 ms

D:\JAVA>java MatchesCount
s.length()=32760, cnt=10000000, done at 5860 ms

D:\JAVA>java MatchesCount 256000
s.length()=256000, cnt=10000000, done at 5594 ms

D:\JAVA>java MatchesCount 512000
s.length()=512000, cnt=10000000, done at 5735 ms