崔华基于oracle的SQL优化读书笔记如何得到真实的执行计划

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得到目标SQL的执行计划,大致有以下四种方式:

1.explain plan 命令

2.DBMS_XPLAN包

3.SQLPLUS中的autotrace开关

4.10046事件

除了第四种,其他三种方法都有可能是不准的。判断一个sq计划任务任务是否准确,就要看目标SQL是否真正被执行。

第一种方法在目标SQL含有绑定变量时不准

第二种方法包里含有四种方式,记住以下三种:

select * from table(dbms_xplan.display_cursor(null,null,‘advanced‘));

select * from table(dbms_xplan.display_cursor(‘sql_id/hash_value‘,child_cursor_number,‘advanced‘));

select * from table(dbms_xplan.display_awr(‘sql_id‘)); --用于已经被age out 出shared pool的情况

第三种方法,SET AUTOTRACE ON 和 SET AUTOTRACE TRACERONLY执行后可看到实际执行情况(计划可能不准,因为SET ATUOTRACE命令都是来源于调用explain plan命令

对于SET AUTOTRACE TRACE TRACEONLY EXPLAIN时,DML语句将会被执行。

此外printsql存储过程也可用于查看实际的执行计划,使用topas等命令查看sql的PID

输入命令exec printsql(1212576,‘SPID‘); 

可得到sql、真实的执行计划以及杀死这个session的语句。具体语句见文末。

最后就是通过AWR(适合10g及其以上版本)报告了,通过命令@’$ORACLE_HOME/rdbms/admin/awrsqrpt.sql‘;

依次输入 text、1(天数,指最近一天)、起始快照时间、终止快照时间、目标sqlID

 

printsql内容,文件名为PRINTSQL.prc_

create or replace procedure PRINTSQL
(i_n_id in number,
 i_vc_idtype in varchar2) is
/*
功能: 打印对应spid或sid所对应的sql以及其执行计划
作者: 老熊,dbsnake
创建日期:2010-11-12

输入参数:
i_n_id: 输入的spid或sid
i_vc_idtype : 输入的ID的类型,‘SPID‘表示输入的是spid,‘SID‘表示输入的是sid.

输出参数:

输入输出参数:

调用到的存储过程:

*/

o_vc_return_flag varchar2(4000);

type typsqltext is table of varchar2(1000) index by binary_integer;
typsqltexts typsqltext;

vc_paddr varchar2(4000);
n_hashvalue number;
n_childnumber number;
rec_session v$session%rowtype;
rec_sessionwait v$session_wait%rowtype;
rec_sql v$sql%rowtype;

/*select hash_value,child_number,plan_hash_value,executions,buffer_gets,buffer_gets/decode(executions,0,1,executions) gets_per_exec,
rows_processed,rows_processed/decode(executions,0,1,executions) rows_per_exec,
disk_reads,disk_reads/decode(executions,0,1,executions)  reads_per_exec,
cpu_time/1000000 cpu_time,cpu_time/decode(executions,0,1,executions)/1000000 cpu_per_exec,
ELAPSED_TIME/1000000 ELAPSED_TIME,ELAPSED_TIME/decode(executions,0,1,executions)/1000000 ela_per_exec
from v$sql where hash_value=&1
and rownum<=100;*/

type type_hash_value is table of v$sql.HASH_VALUE%type index by binary_integer;
hash_values type_hash_value;
type type_child_number is table of v$sql.CHILD_NUMBER%type index by binary_integer;
child_numbers type_child_number;
type type_plan_hash_value is table of v$sql.PLAN_HASH_VALUE%type index by binary_integer;
plan_hash_values type_plan_hash_value;
type type_execution is table of v$sql.EXECUTIONS%type index by binary_integer;
executions type_execution;
type type_buffer_get is table of v$sql.BUFFER_GETS%type index by binary_integer;
buffer_gets type_buffer_get;
type type_gets_per_exec is table of v$sql.BUFFER_GETS%type index by binary_integer;
gets_per_execs type_gets_per_exec;
type type_rows_processed is table of v$sql.ROWS_PROCESSED%type index by binary_integer;
rows_processeds type_rows_processed;
type type_rows_per_exec is table of v$sql.ROWS_PROCESSED%type index by binary_integer;
rows_per_execs type_rows_per_exec;
type type_disk_read is table of v$sql.DISK_READS%type index by binary_integer;
disk_reads type_disk_read;
type type_reads_per_exec is table of v$sql.DISK_READS%type index by binary_integer;
reads_per_execs type_reads_per_exec;
type type_cpu_time is table of v$sql.CPU_TIME%type index by binary_integer;
cpu_times type_cpu_time;
type type_cpu_per_exec is table of v$sql.CPU_TIME%type index by binary_integer;
cpu_per_execs type_cpu_per_exec;
type type_ELAPSED_TIME is table of v$sql.ELAPSED_TIME%type index by binary_integer;
ELAPSED_TIMEs type_ELAPSED_TIME;
type type_ela_per_exec is table of v$sql.ELAPSED_TIME%type index by binary_integer;
ela_per_execs type_ela_per_exec;


-- cursor c_display_cursor(in_address varchar2, in_hash_value number, in_child_number number) is
s_display_cursor varchar2(32767) := ‘
select case when access_predicates is not null or filter_predicates is not null then ‘‘*‘‘ else ‘‘ ‘‘ end || substr(to_char(id, ‘‘999‘‘), -3) as p_id,
lpad(‘‘ ‘‘, depth) || operation || ‘‘ ‘‘ || options as operation,
object_name as name,
starts,
cardinality as e_rows,
outrows as a_rows,
to_char(to_number(substr(e_time_interval, 2, 9)) * 24 + to_number(substr(e_time_interval, 12, 2)), ‘‘FM900‘‘) || substr(e_time_interval, 14, 9) as a_time,
crgets + cugets as buffers,
case reads when 0 then null else reads end as reads,
case writes when 0 then null else writes end as writes,
case other_tag
when ‘‘PARALLEL_TO_SERIAL‘‘ then ‘‘P->S‘‘
when ‘‘PARALLEL_COMBINED_WITH_PARENT‘‘ then ‘‘PCWP‘‘
when ‘‘PARALLEL_COMBINED_WITH_CHILD‘‘ then ‘‘PCWC‘‘
when ‘‘SERIAL_TO_PARALLEL‘‘ then ‘‘S->P‘‘
when ‘‘PARALLEL_TO_PARALLEL‘‘ then ‘‘P->P‘‘
when ‘‘PARALLEL_FROM_SERIAL‘‘ then ‘‘P<-S‘‘
else other_tag end as in_out,
partition_start,
partition_stop,
distribution,
mem_opt,
mem_one,
last_mem_used || case last_mem_usage when ‘‘OPTIMAL‘‘ then ‘‘ (0)‘‘ when ‘‘ONE PASS‘‘ then ‘‘ (1)‘‘ when ‘‘MULTI-PASS‘‘ then ‘‘ (M)‘‘ end,
case last_degree when 0 then null when 1 then null else last_degree end as last_degree,
--opt_cnt,
--one_cnt,
--multi_cnt,
--max_tmp,
last_tmp,
access_predicates,
filter_predicates,
dynamic_sampling_flag,
id
from (
SELECT /*+ opt_param(‘‘parallel_execution_enabled‘‘, ‘‘false‘‘) */
                      id, position, depth , operation, options, object_name, cardinality, bytes, temp_space, cost, io_cost,
                      cpu_cost, partition_start, partition_stop, object_node, other_tag, distribution, null, access_predicates, filter_predicates,
                      null, null, null, starts, outrows, crgets, cugets, reads, writes, etime, e_time_interval, mem_opt, mem_one, last_mem_used, last_degree, last_mem_usage,
                      opt_cnt, one_cnt, multi_cnt, max_tmp, last_tmp, dynamic_sampling_flag from (
                          select /*+ no_merge */
                          id, depth, position, operation, options,
                          cost, cardinality, bytes, object_node,
                          object_name, other_tag, partition_start,
                          partition_stop, distribution, temp_space, io_cost,
                          cpu_cost, filter_predicates, access_predicates, other,
                          last_starts starts,
                                    last_output_rows outrows,
                                    last_cr_buffer_gets crgets,
                                    last_cu_buffer_gets cugets,
                                    last_disk_reads reads,
                                    last_disk_writes writes,
                                    last_elapsed_time etime,
                                    to_char(numtodsinterval(round(last_elapsed_time/10000)*10000/1000000, ‘‘SECOND‘‘)) as e_time_interval,
                                    estimated_optimal_size mem_opt,
                                    estimated_onepass_size mem_one,
                                    last_memory_used last_mem_used,
                                    last_degree,
                                    last_execution last_mem_usage,
                                    optimal_executions opt_cnt,
                                    onepass_executions one_cnt,
                                    multipasses_executions multi_cnt,
                                    max_tempseg_size max_tmp,
                                    last_tempseg_size last_tmp,
                                    case 0 /*instr(other_xml, ‘‘dynamic_sampling‘‘)*/ when 0 then NULL else ‘‘YES‘‘ end as dynamic_sampling_flag
              from V$SQL_PLAN_STATISTICS_ALL vp
              --where address = hextoraw(:in_address)
              where hash_value = :in_hash_value
              and child_number = :in_child_number)
)
order by id‘;

s_display_cursor2 varchar2(32767) := ‘
select case when access_predicates is not null or filter_predicates is not null then ‘‘*‘‘ else ‘‘ ‘‘ end || substr(to_char(id, ‘‘999‘‘), -3) as p_id,
lpad(‘‘ ‘‘, depth) || operation || ‘‘ ‘‘ || options as operation,
object_name as name,
cardinality as e_rows,
bytes,
temp_space,
cost,
cpu_cost,
object_node,
case other_tag
when ‘‘PARALLEL_TO_SERIAL‘‘ then ‘‘P->S‘‘
when ‘‘PARALLEL_COMBINED_WITH_PARENT‘‘ then ‘‘PCWP‘‘
when ‘‘PARALLEL_COMBINED_WITH_CHILD‘‘ then ‘‘PCWC‘‘
when ‘‘SERIAL_TO_PARALLEL‘‘ then ‘‘S->P‘‘
when ‘‘PARALLEL_TO_PARALLEL‘‘ then ‘‘P->P‘‘
when ‘‘PARALLEL_FROM_SERIAL‘‘ then ‘‘P<-S‘‘
else other_tag end as in_out,
partition_start,
partition_stop,
distribution,
access_predicates,
filter_predicates,
dynamic_sampling_flag,
id
from (
SELECT /*+ opt_param(‘‘parallel_execution_enabled‘‘, ‘‘false‘‘) */
                      id, position, depth , operation, options, object_name, cardinality, bytes, temp_space, cost, io_cost,
                      cpu_cost, partition_start, partition_stop, object_node, other_tag, distribution, null, access_predicates, filter_predicates,
                      null, null, null, starts, outrows, crgets, cugets, reads, writes, etime, e_time_interval, mem_opt, mem_one, last_mem_used, last_degree, last_mem_usage,
                      opt_cnt, one_cnt, multi_cnt, max_tmp, last_tmp, dynamic_sampling_flag from (
                          select /*+ no_merge */
                          id, depth, position, operation, options,
                          cost, cardinality, bytes, object_node,
                          object_name, other_tag, partition_start,
                          partition_stop, distribution, temp_space, io_cost,
                          cpu_cost, filter_predicates, access_predicates, other,
                          0 starts,
                                    0 outrows,
                                    0 crgets,
                                    0 cugets,
                                    0 reads,
                                    0 writes,
                                    0 etime,
                                    0 e_time_interval,
                                    0 mem_opt,
                                    0 mem_one,
                                    null last_mem_used,
                                    0 last_degree,
                                    null last_mem_usage,
                                    0 opt_cnt,
                                    0 one_cnt,
                                    0 multi_cnt,
                                    0 max_tmp,
                                    0 last_tmp,
                                    case 0 /*instr(other_xml, ‘‘dynamic_sampling‘‘)*/ when 0 then NULL else ‘‘YES‘‘ end as dynamic_sampling_flag
              from V$SQL_PLAN vp
              --where address = hextoraw(:in_address)
              where hash_value = :in_hash_value
              and child_number = :in_child_number)
)
order by id‘;

type t_list_varchar2 is table of varchar2(4000) index by pls_integer;
type t_column_record is record (
a_data        t_list_varchar2,
b_has_data    boolean,
s_heading     varchar2(255),
b_is_number   boolean default false,
s_alignment   varchar2(20),
n_max_size    pls_integer);
type t_column_list is table of t_column_record index by pls_integer;
a_column_list t_column_list;
n_row_size    pls_integer;
s_row         varchar2(4000);
a_access_pred t_list_varchar2;
a_filter_pred t_list_varchar2;
s_plan_hash   varchar2(255);
a_dyn_sampl   t_list_varchar2;
a_id_list     t_list_varchar2;
s_output      varchar2(32767);
s_sql_address varchar2(255);
s_hash_value  varchar2(255);
s_child_num   varchar2(255);
b_has_stat boolean := TRUE;

max_line_size constant pls_integer := 255;
c_display_cursor sys_refcursor;
n_cnt pls_integer;

function has_collection_only_nulls(in_coll in t_list_varchar2)
return boolean is
  b_return boolean := true;
begin
  if in_coll.count > 0 then
    for i in in_coll.first..in_coll.last loop
      if in_coll(i) is not null then
        b_return := false;
        exit;
      end if;
    end loop;
  end if;
  return b_return;
end has_collection_only_nulls;

function get_max_size(in_coll in t_list_varchar2)
return pls_integer is
  n_return pls_integer := 0;
begin
  if in_coll.count > 0 then
    for i in in_coll.first..in_coll.last loop
      if in_coll(i) is not null then
        n_return := greatest(n_return, length(in_coll(i)));
      end if;
    end loop;
  end if;
  return n_return;
end get_max_size;

function display_cursor_format_number(in_data in varchar2)
return varchar2 is
  s_return varchar2(20);
  s_trail varchar2(32767);
  s_data varchar2(32767);
  n_number number;
  n_delim_pos number;
  e_num_val_error exception;
  pragma exception_init(e_num_val_error, -6502);
begin
  n_delim_pos := instr(in_data, ‘ ‘);
  if n_delim_pos > 0 then
    s_trail := substr(in_data, n_delim_pos);
    s_data := substr(in_data, 1, n_delim_pos - 1);
  else
    s_data := in_data;
  end if;
  n_number := to_number(s_data);
  s_return :=
  case
  when n_number >= 100000000000000000000 then to_char(n_number/1000000000000000000, ‘FM99999‘) || ‘E‘
  when n_number >= 100000000000000000 then to_char(n_number/1000000000000000, ‘FM99999‘) || ‘P‘
  when n_number >= 100000000000000 then to_char(n_number/1000000000000, ‘FM99999‘) || ‘T‘
  when n_number >= 100000000000 then to_char(n_number/1000000000, ‘FM99999‘) || ‘G‘
  when n_number >= 100000000 then to_char(n_number/1000000, ‘FM99999‘) || ‘M‘
  when n_number >= 100000 then to_char(n_number/1000, ‘FM99999‘) || ‘K‘
  else to_char(n_number, ‘FM99999‘)
  end;
  return s_return || s_trail;
exception
when e_num_val_error then
  return in_data;
end display_cursor_format_number;

procedure put_line_smart(in_string in varchar2, in_line_prefix in varchar2 default ‘‘, in_line_size in pls_integer default 180) is
  n_offset pls_integer;
  s_delimiter varchar2(1);
  n_size_current_line pls_integer;
  n_line_counter pls_integer;
begin
  n_offset := 1;
  n_size_current_line := in_line_size;
  n_line_counter := 1;
  while case when n_line_counter > 1 and length(in_line_prefix) > 0
        then length(in_string) + length(in_line_prefix)
        else length(in_string) end
        + 1 - n_offset > in_line_size loop
    -- dbms_output.put_line(‘Debug n_offset: ‘ || n_offset);
    if n_line_counter > 1 and length(in_line_prefix) > 0 then
      n_size_current_line := greatest(n_size_current_line - length(in_line_prefix), length(in_line_prefix) + 10);
    end if;
    -- dbms_output.put_line(‘Debug n_size_current_line: ‘ || n_size_current_line);
    loop
      s_delimiter := substr(in_string, n_offset - 1 + n_size_current_line, 1);
      exit when s_delimiter in (‘ ‘, chr(9), chr(10), chr(13)/*, ‘(‘, ‘)‘, ‘[‘, ‘]‘*/) or n_size_current_line < 1;
      n_size_current_line := n_size_current_line - 1;
    end loop;
    if n_size_current_line < 1 then
      if n_line_counter > 1 and length(in_line_prefix) > 0 then
        n_size_current_line := greatest(n_size_current_line - length(in_line_prefix), length(in_line_prefix) + 10);
      else
        n_size_current_line := in_line_size;
      end if;
    end if;
    if s_delimiter in (chr(13), chr(10)) then
      n_size_current_line := n_size_current_line - 1;
    end if;
    dbms_output.put_line(case when n_line_counter > 1 then in_line_prefix end || substr(in_string, n_offset, n_size_current_line));
    if s_delimiter in (chr(13), chr(10)) then
      while substr(in_string, n_offset - 1 + n_size_current_line, 1) in (chr(10), chr(13)) loop
        n_size_current_line := n_size_current_line + 1;
      end loop;
    end if;
    n_offset := n_offset + n_size_current_line;
    n_size_current_line := in_line_size;
    n_line_counter := n_line_counter + 1;
  end loop;
  dbms_output.put_line(case when n_line_counter > 1 then in_line_prefix end || substr(in_string, n_offset));
end put_line_smart;

begin

  dbms_output.put_line(‘--------------------------------------------------------------------------------------‘);

  if ( upper(i_vc_idtype) = ‘SPID‘ ) then
    select addr into vc_paddr from v$process where spid=to_char(i_n_id);
    select * into rec_session from v$session where paddr=vc_paddr;
    select * into rec_sessionwait from v$session_wait where sid=rec_session.SID;
    select decode(sql_hash_value,0,prev_hash_value,sql_hash_value) into n_hashvalue from v$session where sid=rec_session.SID;
    select sql_text bulk collect into typsqltexts from v$sqltext where hash_value=n_hashvalue order by piece;

    if ( typsqltexts.count > 0 ) then
      for i in typsqltexts.first .. typsqltexts.last loop
          ---这里处理掉"dbms_output.put_line"不能处理超过255个字符的限制,并且考虑到了sql语句中可能有中文
          loop
          exit when typsqltexts(i) is null;
            dbms_output.put_line( substrb( typsqltexts(i), 1, 254 ) );
            typsqltexts(i) := substrb( typsqltexts(i), 255 );
          end loop;
      end loop;
    else
      dbms_output.put_line(‘The sql text has been aged out from the shared pool.‘);
    end if;
  elsif ( upper(i_vc_idtype) = ‘SID‘ ) then
    select * into rec_session from v$session where sid=i_n_id;
    select decode(sql_hash_value,0,prev_hash_value,sql_hash_value) into n_hashvalue from v$session where sid=i_n_id;
    select sql_text bulk collect into typsqltexts from v$sqltext where hash_value=n_hashvalue order by piece;

    if ( typsqltexts.count > 0 ) then
      for i in typsqltexts.first .. typsqltexts.last loop
          ---这里处理掉"dbms_output.put_line"不能处理超过255个字符的限制,并且考虑到了sql语句中可能有中文
          loop
          exit when typsqltexts(i) is null;
            dbms_output.put_line( substrb( typsqltexts(i), 1, 254 ) );
            typsqltexts(i) := substrb( typsqltexts(i), 255 );
          end loop;
      end loop;
    else
      dbms_output.put_line(‘The sql text has been aged out from the shared pool.‘);
    end if;
  else
    dbms_output.put_line(‘invalid input id type parameter!‘);
    return;
  end if;

  dbms_output.put_line(‘--------------------------------------------------------------------------------------‘);
  dbms_output.put_line(‘The session id is ‘ || rec_session.SID);
  dbms_output.put_line(‘The status is ‘ || rec_session.STATUS);
  dbms_output.put_line(‘The sql hash value is ‘ || rec_session.SQL_HASH_VALUE);
  --dbms_output.put_line(‘The child cursor number is ‘ || rec_session.SQL_CHILD_NUMBER);
  dbms_output.put_line(‘The prev hash value is ‘ || rec_session.PREV_HASH_VALUE);
  --dbms_output.put_line(‘The prev child cursor number is ‘ || rec_session.PREV_CHILD_NUMBER);
  dbms_output.put_line(‘The osuser is ‘ || rec_session.OSUSER);
  dbms_output.put_line(‘The machine is ‘ || rec_session.MACHINE);
  dbms_output.put_line(‘The terminal is ‘ || rec_session.TERMINAL);
  dbms_output.put_line(‘The program is ‘ || rec_session.PROGRAM);
  dbms_output.put_line(‘The event is ‘ || rec_sessionwait.EVENT);
  dbms_output.put_line(‘--------------------------------------------------------------------------------------‘);

  --demo: alter system kill session ‘417,21188‘ immediate;
  dbms_output.put_line(‘alter system kill session ‘‘‘ || rec_session.SID || ‘,‘ || rec_session.SERIAL# || ‘‘‘ immediate;‘);

  select hash_value,child_number,plan_hash_value,executions,buffer_gets,buffer_gets/decode(executions,0,1,executions) gets_per_exec,
    rows_processed,rows_processed/decode(executions,0,1,executions) rows_per_exec,
    disk_reads,disk_reads/decode(executions,0,1,executions)  reads_per_exec,
    cpu_time/1000000 cpu_time,cpu_time/decode(executions,0,1,executions)/1000000 cpu_per_exec,
    ELAPSED_TIME/1000000 ELAPSED_TIME,ELAPSED_TIME/decode(executions,0,1,executions)/1000000 ela_per_exec
    bulk collect into hash_values,child_numbers,plan_hash_values,executions,buffer_gets,gets_per_execs,
    rows_processeds,rows_per_execs,disk_reads,reads_per_execs,cpu_times,cpu_per_execs,ELAPSED_TIMEs,ela_per_execs
    from v$sql where hash_value=n_hashvalue and rownum<=100;

  if( hash_values.count > 0 ) then
    for i in hash_values.first .. hash_values.last loop
    
     dbms_output.put_line(‘--------------------------------------------------------------------------------------‘);
     dbms_output.put_line(‘The hash_value is ‘ || hash_values(i));
     dbms_output.put_line(‘The child_number is ‘ || child_numbers(i));
     dbms_output.put_line(‘The plan_hash_value is ‘ || plan_hash_values(i));
     dbms_output.put_line(‘The execution is ‘ || executions(i));
     dbms_output.put_line(‘The buffer_gets is ‘ || buffer_gets(i));
     dbms_output.put_line(‘The gets_per_exec is ‘ || gets_per_execs(i));
     dbms_output.put_line(‘The rows_processed is ‘ || rows_processeds(i));
     dbms_output.put_line(‘The rows_per_exec is ‘ || rows_per_execs(i));
     dbms_output.put_line(‘The disk_reads is ‘ || disk_reads(i));
     dbms_output.put_line(‘The reads_per_exec is ‘ || reads_per_execs(i));
     dbms_output.put_line(‘The cpu_time is ‘ || cpu_times(i));
     dbms_output.put_line(‘The cpu_per_exec is ‘ || cpu_per_execs(i));
     dbms_output.put_line(‘The ELAPSED_TIME is ‘ || ELAPSED_TIMEs(i));
     dbms_output.put_line(‘The ela_per_exec is ‘ || ela_per_execs(i));
     dbms_output.put_line(‘--------------------------------------------------------------------------------------‘);
    
      s_hash_value := n_hashvalue;
      s_child_num := child_numbers(i);
      -- Header information
      dbms_output.put_line(chr(13));
      put_line_smart(in_string => ‘ HASH_VALUE: ‘ || s_hash_value || ‘   CHILD_NUMBER: ‘ || s_child_num , in_line_size => max_line_size);
      put_line_smart(in_string => ‘---------------------------------------------------------------------------------------------------------------------------------------------‘, in_line_size => max_line_size);
      begin
       execute immediate ‘
        select sql_text,
        plan_hash_value
        from v$sql
        where hash_value = to_number(:s_hash_value)
        and child_number = to_number(:s_child_num)‘
        into s_output, s_plan_hash using s_hash_value, s_child_num;
      exception
      when NO_DATA_FOUND then
        null;
      when others then
        dbms_output.put_line(‘Error getting SQL text from V$SQL, check privileges‘);
      end;
   
      put_line_smart(s_output);
      dbms_output.put_line(chr(13));
      open c_display_cursor for s_display_cursor using to_number(s_hash_value), to_number(s_child_num);
   
      n_cnt := 1;
   
      fetch c_display_cursor into
        a_column_list(1).a_data(n_cnt), -- a_p_id(n_cnt),
        a_column_list(2).a_data(n_cnt), -- a_operation(n_cnt),
        a_column_list(3).a_data(n_cnt), -- a_name(n_cnt),
        a_column_list(4).a_data(n_cnt), -- a_starts(n_cnt),
        a_column_list(5).a_data(n_cnt), -- a_e_rows(n_cnt),
        a_column_list(6).a_data(n_cnt), -- a_a_rows(n_cnt),
        a_column_list(7).a_data(n_cnt), -- a_a_time(n_cnt),
        a_column_list(8).a_data(n_cnt), -- a_buffers(n_cnt),
        a_column_list(9).a_data(n_cnt), -- a_reads(n_cnt),
        a_column_list(10).a_data(n_cnt), -- a_writes(n_cnt),
        a_column_list(11).a_data(n_cnt), -- a_in_out(n_cnt),
        a_column_list(12).a_data(n_cnt), -- a_partition_start(n_cnt),
        a_column_list(13).a_data(n_cnt), -- a_partition_stop(n_cnt),
        a_column_list(14).a_data(n_cnt), -- a_distribution(n_cnt),
        a_column_list(15).a_data(n_cnt), -- a_last_mem_usage(n_cnt),
        a_column_list(16).a_data(n_cnt), -- a_last_degree(n_cnt),
        a_column_list(17).a_data(n_cnt), -- a_mem_opt(n_cnt),
        a_column_list(18).a_data(n_cnt), -- a_mem_one(n_cnt),
        --a_column_list(17).a_data(n_cnt), -- a_opt_cnt(n_cnt),
        --a_column_list(18).a_data(n_cnt), -- a_one_cnt(n_cnt),
        --a_column_list(19).a_data(n_cnt), -- a_multi_cnt(n_cnt),
        --a_column_list(22).a_data(n_cnt), -- a_max_tmp(n_cnt),
        a_column_list(19).a_data(n_cnt), -- a_last_tmp(n_cnt),
        a_access_pred(n_cnt),
        a_filter_pred(n_cnt),
        a_dyn_sampl(n_cnt),
        a_id_list(n_cnt);
   
      if c_display_cursor%notfound then
         close c_display_cursor;
         --dbms_output.put_line(‘Debug : Select V$SQL_PLAN‘);
         b_has_stat := FALSE;
   
         a_column_list(1).s_heading := ‘Id‘; --a_column_list(1).b_is_number := true;
         a_column_list(2).s_heading := ‘Operation‘;
         a_column_list(3).s_heading := ‘Name‘;
         a_column_list(4).s_heading := ‘Rows‘; a_column_list(4).b_is_number := true;
         a_column_list(5).s_heading := ‘Bytes‘; a_column_list(5).b_is_number := true;
         a_column_list(6).s_heading := ‘TempSpc‘; a_column_list(6).b_is_number := true;
         a_column_list(7).s_heading := ‘Cost‘;a_column_list(7).b_is_number := true;
         a_column_list(8).s_heading := ‘Cpu-Cost‘;a_column_list(8).b_is_number := true;
         a_column_list(9).s_heading := ‘TQ‘;
         a_column_list(10).s_heading := ‘In-Out‘;
         a_column_list(11).s_heading := ‘Pstart‘; a_column_list(10).b_is_number := true;
         a_column_list(12).s_heading := ‘Pstop‘; a_column_list(11).b_is_number := true;
         a_column_list(13).s_heading := ‘PQ Distrib‘;
   
         open c_display_cursor for s_display_cursor2 using to_number(s_hash_value), to_number(s_child_num);
         n_cnt := 0;
      else
         -- The plan statistics
         a_column_list(1).s_heading := ‘Id‘; --a_column_list(1).b_is_number := true;
         a_column_list(2).s_heading := ‘Operation‘;
         a_column_list(3).s_heading := ‘Name‘;
         a_column_list(4).s_heading := ‘Starts‘; a_column_list(4).b_is_number := true;
         a_column_list(5).s_heading := ‘E-Rows‘; a_column_list(5).b_is_number := true;
         a_column_list(6).s_heading := ‘A-Rows‘; a_column_list(6).b_is_number := true;
         a_column_list(7).s_heading := ‘A-Time‘;
         a_column_list(8).s_heading := ‘Buffers‘; a_column_list(8).b_is_number := true;
         a_column_list(9).s_heading := ‘Reads‘; a_column_list(9).b_is_number := true;
         a_column_list(10).s_heading := ‘Writes‘; a_column_list(10).b_is_number := true;
         a_column_list(11).s_heading := ‘In-Out‘;
         a_column_list(12).s_heading := ‘Pstart‘; a_column_list(12).b_is_number := true;
         a_column_list(13).s_heading := ‘Pstop‘; a_column_list(13).b_is_number := true;
         a_column_list(14).s_heading := ‘PQ Distrib‘;
         a_column_list(15).s_heading := ‘OMem‘; a_column_list(15).b_is_number := true;
         a_column_list(16).s_heading := ‘1Mem‘; a_column_list(16).b_is_number := true;
         a_column_list(17).s_heading := ‘Used-Mem‘; a_column_list(17).b_is_number := true; --a_column_list(15).s_alignment := ‘RIGHT‘;
         a_column_list(18).s_heading := ‘Last-Degree‘; a_column_list(18).b_is_number := true;
         --a_column_list(19).s_heading := ‘Opt-Cnt‘; a_column_list(17).b_is_number := true;
         --a_column_list(20).s_heading := ‘One-Cnt‘; a_column_list(18).b_is_number := true;
         --a_column_list(21).s_heading := ‘Multi-Cnt‘; a_column_list(19).b_is_number := true;
         --a_column_list(19).s_heading := ‘Max-Tmp‘; a_column_list(19).b_is_number := true;
         a_column_list(19).s_heading := ‘Last-Tmp‘; a_column_list(19).b_is_number := true;
   
         n_cnt := 1;
      end if;
   
      loop
        exit when c_display_cursor%notfound;
        n_cnt := n_cnt + 1;
        if b_has_stat then
            fetch c_display_cursor into
            a_column_list(1).a_data(n_cnt), -- a_p_id(n_cnt),
            a_column_list(2).a_data(n_cnt), -- a_operation(n_cnt),
            a_column_list(3).a_data(n_cnt), -- a_name(n_cnt),
            a_column_list(4).a_data(n_cnt), -- a_starts(n_cnt),
            a_column_list(5).a_data(n_cnt), -- a_e_rows(n_cnt),
            a_column_list(6).a_data(n_cnt), -- a_a_rows(n_cnt),
            a_column_list(7).a_data(n_cnt), -- a_a_time(n_cnt),
            a_column_list(8).a_data(n_cnt), -- a_buffers(n_cnt),
            a_column_list(9).a_data(n_cnt), -- a_reads(n_cnt),
            a_column_list(10).a_data(n_cnt), -- a_writes(n_cnt),
            a_column_list(11).a_data(n_cnt), -- a_in_out(n_cnt),
            a_column_list(12).a_data(n_cnt), -- a_partition_start(n_cnt),
            a_column_list(13).a_data(n_cnt), -- a_partition_stop(n_cnt),
            a_column_list(14).a_data(n_cnt), -- a_distribution(n_cnt),
            a_column_list(15).a_data(n_cnt), -- a_last_mem_usage(n_cnt),
            a_column_list(16).a_data(n_cnt), -- a_last_degree(n_cnt),
            a_column_list(17).a_data(n_cnt), -- a_mem_opt(n_cnt),
            a_column_list(18).a_data(n_cnt), -- a_mem_one(n_cnt),
            a_column_list(19).a_data(n_cnt), -- a_last_tmp(n_cnt),
            a_access_pred(n_cnt),
            a_filter_pred(n_cnt),
            a_dyn_sampl(n_cnt),
            a_id_list(n_cnt);
        else
            fetch c_display_cursor into
            a_column_list(1).a_data(n_cnt),
            a_column_list(2).a_data(n_cnt),
            a_column_list(3).a_data(n_cnt),
            a_column_list(4).a_data(n_cnt),
            a_column_list(5).a_data(n_cnt),
            a_column_list(6).a_data(n_cnt),
            a_column_list(7).a_data(n_cnt),
            a_column_list(8).a_data(n_cnt),
            a_column_list(9).a_data(n_cnt),
            a_column_list(10).a_data(n_cnt),
            a_column_list(11).a_data(n_cnt),
            a_column_list(12).a_data(n_cnt),
            a_column_list(13).a_data(n_cnt),
            a_access_pred(n_cnt),
            a_filter_pred(n_cnt),
            a_dyn_sampl(n_cnt),
            a_id_list(n_cnt);
         end if;
      end loop;
   
      close c_display_cursor;
      if a_column_list(1).a_data.count > 0 then
        dbms_output.put_line(‘Plan hash value: ‘ || s_plan_hash);
        dbms_output.put_line(chr(13));
        n_row_size := 1;
        for i in a_column_list.first..a_column_list.last loop
          if a_column_list(i).b_is_number then
            if a_column_list(i).a_data.count > 0 then
              for j in a_column_list(i).a_data.first..a_column_list(i).a_data.last loop
                begin
                  a_column_list(i).a_data(j) := display_cursor_format_number(a_column_list(i).a_data(j));
                exception
                when others then
                  dbms_output.put_line(‘Column:‘ || a_column_list(i).s_heading || ‘ Data: ‘ || a_column_list(i).a_data(j));
                  raise;
                end;
              end loop;
            end if;
          end if;
          -- column size is greatest of max size of content + 2 (leading + trailing blanks) and size of column heading
          a_column_list(i).n_max_size := greatest(get_max_size(a_column_list(i).a_data) + 2, length(a_column_list(i).s_heading) + 2);
          a_column_list(i).b_has_data := not has_collection_only_nulls(a_column_list(i).a_data);
          if a_column_list(i).b_has_data then
            n_row_size := n_row_size + a_column_list(i).n_max_size + 1;
          end if;
        end loop;
        -- Header
        put_line_smart(in_string => lpad(‘-‘, n_row_size, ‘-‘), in_line_size => max_line_size);
        s_row := ‘‘;
        for i in a_column_list.first..a_column_list.last loop
          if a_column_list(i).b_has_data then
            if a_column_list(i).s_alignment is null then
              if a_column_list(i).b_is_number then
                s_row := s_row || ‘|‘ || lpad(a_column_list(i).s_heading, a_column_list(i).n_max_size - 1) || ‘ ‘;
              else
                s_row := s_row || ‘|‘ || ‘ ‘ || rpad(a_column_list(i).s_heading, a_column_list(i).n_max_size - 1);
              end if;
            else
              if a_column_list(i).s_alignment = ‘RIGHT‘ then
                s_row := s_row || ‘|‘ || lpad(a_column_list(i).s_heading, a_column_list(i).n_max_size - 1) || ‘ ‘;
              else
                s_row := s_row || ‘|‘ || ‘ ‘ || rpad(a_column_list(i).s_heading, a_column_list(i).n_max_size - 1);
              end if;
            end if;
          end if;
        end loop;
        s_row := s_row || ‘|‘;
        put_line_smart(in_string => s_row, in_line_size => max_line_size);
        -- Data
        put_line_smart(in_string => lpad(‘-‘, n_row_size, ‘-‘), in_line_size => max_line_size);
        for j in a_column_list(1).a_data.first..a_column_list(1).a_data.last loop
          s_row := ‘‘;
          for i in a_column_list.first..a_column_list.last loop
            if a_column_list(i).b_has_data then
              if a_column_list(i).b_is_number then
                s_row := s_row || ‘|‘ || lpad(nvl(a_column_list(i).a_data(j), ‘ ‘), a_column_list(i).n_max_size - 1) || ‘ ‘;
              else
                s_row := s_row || ‘|‘ || ‘ ‘ || rpad(nvl(a_column_list(i).a_data(j), ‘ ‘), a_column_list(i).n_max_size - 1);
              end if;
            end if;
          end loop;
          s_row := s_row || ‘|‘;
          put_line_smart(in_string => s_row, in_line_size => max_line_size);
        end loop;
        -- Footer
        put_line_smart(in_string => lpad(‘-‘, n_row_size, ‘-‘), in_line_size => max_line_size);
        -- Predicate information
        dbms_output.put_line(chr(13));
        dbms_output.put_line(‘Predicate Information (identified by operation id):‘);
        dbms_output.put_line(‘---------------------------------------------------‘);
        for j in a_column_list(1).a_data.first..a_column_list(1).a_data.last loop
          if a_access_pred(j) is not null or a_filter_pred(j) is not null then
            s_output := lpad(to_char(to_number(a_id_list(j)), ‘FM9999‘), 4, ‘ ‘) || ‘ - ‘;
            if a_access_pred(j) is not null then
              put_line_smart(s_output || ‘access(‘ || a_access_pred(j) || ‘)‘, lpad(‘ ‘, length(s_output), ‘ ‘));
            end if;
            if a_filter_pred(j) is not null then
              if a_access_pred(j) is not null then
                put_line_smart(lpad(‘ ‘, length(s_output), ‘ ‘) || ‘filter(‘ || a_filter_pred(j) || ‘)‘, lpad(‘ ‘, length(s_output), ‘ ‘));
              else
                put_line_smart(s_output || ‘filter(‘ || a_filter_pred(j) || ‘)‘, lpad(‘ ‘, length(s_output), ‘ ‘));
              end if;
            end if;
          end if;
        end loop;
        --dbms_output.put_line(‘DEBUG:Begin Notes‘);
        -- Notes section
        if not a_column_list(4).b_has_data or a_dyn_sampl(1) = ‘YES‘ then
          dbms_output.put_line(chr(13));
          dbms_output.put_line(‘Note‘);
          dbms_output.put_line(‘-----‘);
        end if;
        if a_dyn_sampl(1) = ‘YES‘ then
          dbms_output.put_line(‘   - dynamic sampling used for this statement‘);
        end if;
        if not a_column_list(4).b_has_data then
          dbms_output.put_line(‘   - Warning: basic plan statistics not available. These are only collected when:‘);
          dbms_output.put_line(‘       * parameter ‘‘statistics_level‘‘ is set to ‘‘ALL‘‘, at session or system level‘);
        end if;
      else
        dbms_output.put_line(‘SQL information could not be found for HASH_VALUE: ‘ || s_hash_value || ‘,CHILD_NUMBER: ‘ || s_child_num);
        dbms_output.put_line(‘Please verify value of SQL address, hash_value and child_number;‘);
        dbms_output.put_line(‘It could also be that the plan is no longer in cursor cache (check v$sql_plan)‘);
      end if;

    end loop;
  end if;

exception
  when others then
    o_vc_return_flag := ‘E‘ || ‘_‘ || sqlcode || ‘_‘ || sqlerrm;
    dbms_output.put_line(o_vc_return_flag);
    return;

end PRINTSQL;
/

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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