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 Window (Analytical) FunctionsContext Variables 

Procedure SET_FLUSH_INTERVAL

RDB$PROFILER.SET_FLUSH_INTERVAL turns periodic auto-flush on (when FLUSH_INTERVAL is greater than 0) or off (when FLUSH_INTERVAL is equal to 0).

FLUSH_INTERVAL is interpreted as number of seconds.

Input parameters

  • FLUSH_INTERVAL type INTEGER NOT NULL

  • ATTACHMENT_ID type BIGINT NOT NULL default CURRENT_CONNECTION

Example

Below is a sample profile session and queries for data analysis.

  1. Preparation — create table and routines that will be analyzed

    create table tab (
    id integer not null,
    val integer not null
);

set term !;

create or alter function mult(p1 integer, p2 integer) returns integer
as
begin
    return p1 * p2;
end!

create or alter procedure ins
as
    declare n integer = 1;
begin
    while (n <= 1000)
    do
    begin
        if (mod(n, 2) = 1) then
            insert into tab values (:n, mult(:n, 2));
        n = n + 1;
    end
end!

set term ;!

  2. Start profiling

    select rdb$profiler.start_session('Profile Session 1') from rdb$database;

set term !;

execute block
as
begin
    execute procedure ins;
    delete from tab;
end!

set term ;!

execute procedure rdb$profiler.finish_session(true);

execute procedure ins;

select rdb$profiler.start_session('Profile Session 2') from rdb$database;

select mod(id, 5),
       sum(val)
  from tab
  where id <= 50
  group by mod(id, 5)
  order by sum(val);

execute procedure rdb$profiler.finish_session(true);

  3. Data analysis

    set transaction read committed;

select * from plg$prof_sessions;

select * from plg$prof_psql_stats_view;

select * from plg$prof_record_source_stats_view;

select preq.*
  from plg$prof_requests preq
  join plg$prof_sessions pses
    on pses.profile_id = preq.profile_id and
       pses.description = 'Profile Session 1';

select pstat.*
  from plg$prof_psql_stats pstat
  join plg$prof_sessions pses
    on pses.profile_id = pstat.profile_id and
       pses.description = 'Profile Session 1'
  order by pstat.profile_id,
           pstat.request_id,
           pstat.line_num,
           pstat.column_num;

select pstat.*
  from plg$prof_record_source_stats pstat
  join plg$prof_sessions pses
    on pses.profile_id = pstat.profile_id and
       pses.description = 'Profile Session 2'
  order by pstat.profile_id,
           pstat.request_id,
           pstat.cursor_id,
           pstat.record_source_id;