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2026-03-12 21:01:38

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Valeriu PLESNILA
2026-03-12 22:01:38 +01:00
parent 3bd1db26cc
commit 26296b6d6a
336 changed files with 27507 additions and 0 deletions
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105
divers/FK_indexing_01.txt Normal file
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drop table SUPPLIER purge;
create table SUPPLIER(
id INTEGER generated always as identity
,name varchar2(30) not null
,primary key(id)
)
;
insert /*+ APPEND */ into SUPPLIER(name)
select
dbms_random.string('x',30)
from
xmltable('1 to 100')
;
commit;
drop table PRODUCT purge;
create table PRODUCT(
id integer generated always as identity
,supplier_id integer
,product_name varchar2(30)
,price NUMBER
,primary key(id)
,constraint fk_prod_suppl foreign key(supplier_id) references SUPPLIER(id) on delete cascade
)
;
alter table PRODUCT drop constraint fk_prod_suppl;
alter table PRODUCT add constraint fk_prod_suppl foreign key(supplier_id) references SUPPLIER(id) on delete cascade;
insert /*+ APPEND */ into PRODUCT(supplier_id,product_name,price)
select
trunc(dbms_random.value(1,90))
,dbms_random.string('x',30)
,dbms_random.value(1,10000)
from
xmltable('1 to 10000000')
;
commit;
-- grant execute on dbms_job to POC;
-- grant create job to POC;
create or replace procedure delete_supplier(suppl_id integer) as
begin
DBMS_APPLICATION_INFO.set_module(module_name => 'delete_supplier', action_name => 'Delete supplier');
delete from SUPPLIER where id=suppl_id;
commit;
end;
/
create or replace procedure parallel_delete_supplier as
v_jobno number:=0;
begin
for i in 51..100 loop
dbms_job.submit(v_jobno,'delete_supplier('||to_char(i)||');', sysdate);
end loop;
commit;
end;
/
-- create a huge locking situation ;)
exec parallel_delete_supplier;
SQL> @ash/ashtop inst_id,session_id,sql_id,event2,blocking_inst_id,blocking_session,blocking_session_status,P1text,p2,p3 "username='POC'" sysdate-1/24/20 sysdate
Total Distinct Distinct
Seconds AAS %This INST_ID SESSION_ID SQL_ID EVENT2 BLOCKING_INST_ID BLOCKING_SESSION BLOCKING_SE P1TEXT P2 P3 FIRST_SEEN LAST_SEEN Execs Seen Tstamps
--------- ------- ------- ---------- ---------- ------------- ------------------------------------------ ---------------- ---------------- ----------- ------------------------------ ---------- ---------- ------------------- ------------------- ---------- --------
15 .1 2% | 1 19 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 20 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 21 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 23 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 25 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 27 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 29 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 30 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 31 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 33 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 35 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 38 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 158 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 159 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
15 .1 2% | 1 160 2b4hjy6xfb76s enq: TM - contention [mode=5] 1 450 VALID name|mode 42238 0 2024-02-11 19:09:40 2024-02-11 19:09:54 1 15
-- find enq mode from P1 column og gv$session
SQL> select distinct' [mode='||BITAND(p1, POWER(2,14)-1)||']' from gv$session where username='POC' and event like 'enq%';
'[MODE='||BITAND(P1,POWER(2,14)-1)||']'
------------------------------------------------
[mode=5]
-- index the FK on child table
create index IDX_PRODUCT_SUPPL_ID on PRODUCT(supplier_id);