🥇Happy Party jew ftit linji ta' memorji dwar kif issir taf il-qsim f'PostgreSQL10

Prefazju jew kif ħarġet l-idea tat-taqsim

L-istorja tibda hawn: Tiftakar kif beda kollox. Kollox kien għall-ewwel darba u għal darb'oħra. Wara li kważi r-riżorsi kollha għall-ottimizzazzjoni tat-talba, f'dak iż-żmien, ġew eżawriti, qamet il-mistoqsija - xi jmiss? Dan huwa kif qamet l-idea ta 'qsim.

Digressjoni lirika:
Preċiżament ‘f’dak il-mument’, għax kif irriżulta, kien hemm riżervi ta 'ottimizzazzjoni mhux sfruttati... Grazzi asmm u Habru!

Allura, kif inkella tista 'tagħmel lill-klijent kuntent, u fl-istess ħin ittejjeb il-ħiliet tiegħek?

Biex tissimplifika kollox kemm jista 'jkun, allura hemm biss żewġ modi biex ittejjeb radikalment xi ħaġa fil-prestazzjoni tad-database:
1) Mogħdija estensiva - aħna nżidu r-riżorsi, nibdlu l-konfigurazzjoni;
2) Mogħdija intensiva - ottimizzazzjoni tal-mistoqsija

Peress li, nerġa 'nagħmel, dak iż-żmien ma kienx għadu ċar x'iktar li jinbidel fit-talba biex titħaffef, it-triq intgħażlet - bidliet fid-disinn tal-mejda.

Allura, tqum il-mistoqsija ewlenija: x'se ninbidlu u kif?

Kundizzjonijiet inizjali

L-ewwelnett, hemm dan l-ERD (muri b'mod simplifikat kondizzjonali):

Karatteristiċi Ewlenin:

relazzjonijiet ħafna għal ħafna
it-tabella diġà għandha ċavetta diviżorja potenzjali

Talba oriġinali:

SELECT
            p."PARAMETER_ID" as  parameter_id,
            pc."PC_NAME" AS pc_name,
            pc."CUSTOMER_PARTNUMBER" AS customer_partnumber,
            w."LASERMARK" AS lasermark,
            w."LOTID" AS lotid,
            w."REPORTED_VALUE" AS reported_value,
            w."LOWER_SPEC_LIMIT" AS lower_spec_limit,
            w."UPPER_SPEC_LIMIT" AS upper_spec_limit,
            p."TYPE_CALCUL" AS type_calcul,
            s."SHIPMENT_NAME" AS shipment_name,
            s."SHIPMENT_DATE" AS shipment_date,
            extract(year from s."SHIPMENT_DATE") AS year,
            extract(month from s."SHIPMENT_DATE") as month,
            s."REPORT_NAME" AS report_name,
            p."SPARAM_NAME" AS SPARAM_name,
            p."CUSTOMERPARAM_NAME" AS customerparam_name
        FROM data w INNER JOIN shipment s ON s."SHIPMENT_ID" = w."SHIPMENT_ID"
             INNER JOIN parameters p ON p."PARAMETER_ID" = w."PARAMETER_ID"
             INNER JOIN shipment_pc sp ON s."SHIPMENT_ID" = sp."SHIPMENT_ID"
             INNER JOIN pc pc ON pc."PC_ID" = sp."PC_ID"
             INNER JOIN ( SELECT w2."LASERMARK" , MAX(s2."SHIPMENT_DATE") AS "SHIPMENT_DATE"
                          FROM shipment s2 INNER JOIN data w2 ON s2."SHIPMENT_ID" = w2."SHIPMENT_ID" 
                          GROUP BY w2."LASERMARK"
                         ) md ON md."SHIPMENT_DATE" = s."SHIPMENT_DATE" AND md."LASERMARK" = w."LASERMARK"
        WHERE 
             s."SHIPMENT_DATE" >= '2018-07-01' AND s."SHIPMENT_DATE" <= '2018-09-30' ;

Riżultati tal-eżekuzzjoni fuq id-database tat-test:
spiża : 502 997.55
Ħin ta' eżekuzzjoni: 505 sekonda.

X'naraw? Talba regolari, ibbażata fuq porzjon tal-ħin.
Ejja nagħmlu l-aktar suppożizzjoni loġika sempliċi: jekk ikun hemm kampjun ta 'porzjon tal-ħin, se jgħinna? Dak id-dritt - qsim.

X'taqsam?

L-ewwel daqqa t'għajn, l-għażla hija ovvja - tqassim dikjarattiv tat-tabella tal-"vjeġġ" bl-użu taċ-ċavetta "SHIPMENT_DATE" (jaqbeż wisq 'il quddiem - fl-aħħar irriżulta ftit ħażin fil-produzzjoni).

Kif taqsim?

Din il-mistoqsija mhix wisq diffiċli. Fortunatament, f'PostgreSQL 10, issa hemm mekkaniżmu ta 'qsim tal-bniedem.
So:

Issejvja dump tat-tabella tas-sors - pg_dump source_table
Ħassar it-tabella oriġinali - qatra tabella source_table
Oħloq tabella ġenitur b'qsim tal-firxa - toħloq tabella source_table
Oħloq sezzjonijiet - toħloq tabella source_table, toħloq indiċi
Importa d-dump maħluqa fil-pass 1 - pg_restore

Skripts għall-qsim

Għal sempliċità u konvenjenza, il-passi 2,3,4 ġew magħquda f'kitba waħda.

So:
Ħlief dump tat-tabella tas-sors

pg_dump postgres --file=/dump/shipment.dmp --format=c --table=shipment --verbose > /dump/shipment.log 2>&1

Ħassar it-tabella tas-sors + Oħloq tabella ġenitur b'qsim ta 'firxa + Oħloq diviżorji

--create_partition_shipment.sql
do language plpgsql $$
declare 
rec_shipment_date RECORD ;
partition_name varchar;
index_name varchar;
current_year varchar ;
current_month varchar ;
begin_year varchar ;
begin_month varchar ;
next_year varchar ;
next_month varchar ;
first_flag boolean ;
i integer ;
begin
  RAISE NOTICE 'CREATE TEMPORARY TABLE FOR SHIPMENT_DATE';
  CREATE TEMP TABLE tmp_shipment_date as select distinct "SHIPMENT_DATE" from shipment order by "SHIPMENT_DATE" ;

  RAISE NOTICE 'DROP TABLE shipment';
  drop table shipment cascade ;
  
  CREATE TABLE public.shipment
  (
    "SHIPMENT_ID" integer NOT NULL DEFAULT nextval('shipment_shipment_id_seq'::regclass),
    "SHIPMENT_NAME" character varying(30) COLLATE pg_catalog."default",
    "SHIPMENT_DATE" timestamp without time zone,
    "REPORT_NAME" character varying(40) COLLATE pg_catalog."default"
  )
  PARTITION BY RANGE ("SHIPMENT_DATE")
  WITH (
      OIDS = FALSE
  )
  TABLESPACE pg_default;

  RAISE NOTICE 'CREATE PARTITIONS FOR TABLE shipment';

  current_year:='0';
  current_month:='0';

  begin_year := '0' ;
  begin_month := '0'  ;
  next_year := '0' ;
  next_month := '0'  ;

  FOR rec_shipment_date IN SELECT * FROM tmp_shipment_date LOOP
      
      RAISE NOTICE 'SHIPMENT_DATE=%',rec_shipment_date."SHIPMENT_DATE";
      
      current_year := date_part('year' ,rec_shipment_date."SHIPMENT_DATE");
      current_month := date_part('month' ,rec_shipment_date."SHIPMENT_DATE") ; 

      IF to_number(current_month,'99') < 10 THEN
        current_month := '0'||current_month ; 
      END IF ;

      --Init borders
      IF   begin_year = '0' THEN
       first_flag := true ; --first time flag
       begin_year := current_year ;
       begin_month := current_month ;   
   
        IF current_month = '12' THEN
          next_year := date_part('year' ,rec_shipment_date."SHIPMENT_DATE" + interval '1 year') ;
        ELSE
          next_year := current_year ;
        END IF;
     
       next_month := date_part('month' ,rec_shipment_date."SHIPMENT_DATE" + interval '1 month') ;

      END IF;

      -- Check current date into borders NOT for First time
      IF to_date( current_year||'.'||current_month, 'YYYY.MM') >= to_date( begin_year||'.'||begin_month, 'YYYY.MM') AND 
         to_date( current_year||'.'||current_month, 'YYYY.MM') < to_date( next_year||'.'||next_month, 'YYYY.MM') AND 
         NOT first_flag 
      THEN
         CONTINUE ; 
      ELSE
       --NEW borders only for second and after time 
       begin_year := current_year ;
       begin_month := current_month ;   
   
        IF current_month = '12' THEN
          next_year := date_part('year' ,rec_shipment_date."SHIPMENT_DATE" + interval '1 year') ;
        ELSE
          next_year := current_year ;
        END IF;
     
       next_month := date_part('month' ,rec_shipment_date."SHIPMENT_DATE" + interval '1 month') ;

      END IF;      

      partition_name := 'shipment_shipment_date_'||begin_year||'-'||begin_month||'-01-'|| next_year||'-'||next_month||'-01'  ;
 
     EXECUTE format('CREATE TABLE ' || quote_ident(partition_name) || ' PARTITION OF shipment FOR VALUES FROM ( %L ) TO ( %L )  ' , current_year||'-'||current_month||'-01' , next_year||'-'||next_month||'-01'  ) ; 

      index_name := partition_name||'_shipment_id_idx';
      RAISE NOTICE 'INDEX NAME =%',index_name;
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_ID") TABLESPACE pg_default ' ) ; 

      --Drop first time flag
      first_flag := false ;
   
  END LOOP;

end
$$;

L-importazzjoni tad-dump

pg_restore -d postgres --data-only --format=c --table=shipment --verbose  shipment.dmp > /tmp/data_dump/shipment_restore.log 2>&1

Iċċekkja r-riżultati tal-qsim

X'għandna bħala riżultat? It-test sħiħ tal-pjan ta 'eżekuzzjoni huwa kbir u boring, għalhekk huwa pjuttost possibbli li tillimita lilek innifsek għan-numri finali.

Kien

Spiża: 502 997.55
Ħin ta' eżekuzzjoni: 505 sekondi.

Sar

Spiża: 77 872.36
Ħin ta' eżekuzzjoni: 79 sekondi.

Riżultat pjuttost tajjeb. Spiża mnaqqsa u ħin ta 'eżekuzzjoni. Għalhekk, l-użu tal-qsim jagħti l-effett mistenni u, b'mod ġenerali, l-ebda sorpriża.

Agħmel il-klijent kuntent

Ir-riżultati tat-test ġew ippreżentati lill-klijent għal reviżjoni. U wara li rrevedewha, ingħataw verdett kemmxejn mhux mistenni: "Kbir, jaqsam it-tabella tad-"data"."

Iva, imma eżaminajna tabella ta' "konsenja" kompletament differenti; it-tabella "data" m'għandhiex il-qasam "SHIPMENT_DATE".

Ebda problema, żid, ibdel. Il-ħaġa prinċipali hija li l-klijent ikun sodisfatt bir-riżultat; id-dettalji tal-implimentazzjoni mhumiex partikolarment importanti.

Il-qsim tat-tabella prinċipali "data"

B'mod ġenerali, ma nqalgħu l-ebda diffikultajiet partikolari. Għalkemm, l-algoritmu tal-qsim, ovvjament, inbidel xi ftit.

Żieda tal-kolonna "SHIPMENT_DATA" mat-tabella "data".

psql -h хост -U база -d юзер
=> ALTER TABLE data ADD COLUMN "SHIPMENT_DATE" timestamp without time zone ;

Imla l-valuri tal-kolonna "SHIPMENT_DATA" fit-tabella "data" bil-valuri tal-kolonna tal-istess isem mit-tabella "shipment"

-----------------------------
--update_data.sql
--updating for altered table "data" to values of "shipment_data" from the table "shipment"
--version 1.0
do language plpgsql $$
declare 
rec_shipment_data RECORD ;
shipment_date timestamp without time zone ; 
row_count integer ;
total_rows integer ;
begin

  select count(*) into total_rows from shipment ; 
  RAISE NOTICE 'Total %',total_rows;
  row_count:= 0 ;

  FOR rec_shipment_data IN SELECT * FROM shipment LOOP

   update data set "SHIPMENT_DATE" = rec_shipment_data."SHIPMENT_DATE" where "SHIPMENT_ID" = rec_shipment_data."SHIPMENT_ID";
   
   row_count:=  row_count +1 ;
   RAISE NOTICE 'row count = % , from %',row_count,total_rows;
  END LOOP;

end
$$;

Issejvja dump tat-tabella tad-“data”.

pg_dump postgres --file=/dump/data.dmp --format=c --table=data --verbose > /dump/data.log 2>&1</source

Oħloq mill-ġdid it-tabella maqsuma "data"

--create_partition_data.sql
--create partitions for the table "wafer data" by range column "shipment_data" with one month duration
--version 1.0
do language plpgsql $$
declare 
rec_shipment_date RECORD ;
partition_name varchar;
index_name varchar;
current_year varchar ;
current_month varchar ;
begin_year varchar ;
begin_month varchar ;
next_year varchar ;
next_month varchar ;
first_flag boolean ;
i integer ;

begin

  RAISE NOTICE 'CREATE TEMPORARY TABLE FOR SHIPMENT_DATE';
  CREATE TEMP TABLE tmp_shipment_date as select distinct "SHIPMENT_DATE" from shipment order by "SHIPMENT_DATE" ;


  RAISE NOTICE 'DROP TABLE data';
  drop table data cascade ;


  RAISE NOTICE 'CREATE PARTITIONED TABLE data';
  
  CREATE TABLE public.data
  (
    "RUN_ID" integer,
    "LASERMARK" character varying(20) COLLATE pg_catalog."default" NOT NULL,
    "LOTID" character varying(80) COLLATE pg_catalog."default",
    "SHIPMENT_ID" integer NOT NULL,
    "PARAMETER_ID" integer NOT NULL,
    "INTERNAL_VALUE" character varying(75) COLLATE pg_catalog."default",
    "REPORTED_VALUE" character varying(75) COLLATE pg_catalog."default",
    "LOWER_SPEC_LIMIT" numeric,
    "UPPER_SPEC_LIMIT" numeric , 
    "SHIPMENT_DATE" timestamp without time zone
  )
  PARTITION BY RANGE ("SHIPMENT_DATE")
  WITH (
    OIDS = FALSE
  )
  TABLESPACE pg_default ;


  RAISE NOTICE 'CREATE PARTITIONS FOR TABLE data';

  current_year:='0';
  current_month:='0';

  begin_year := '0' ;
  begin_month := '0'  ;
  next_year := '0' ;
  next_month := '0'  ;
  i := 1;

  FOR rec_shipment_date IN SELECT * FROM tmp_shipment_date LOOP
      
      RAISE NOTICE 'SHIPMENT_DATE=%',rec_shipment_date."SHIPMENT_DATE";
      
      current_year := date_part('year' ,rec_shipment_date."SHIPMENT_DATE");
      current_month := date_part('month' ,rec_shipment_date."SHIPMENT_DATE") ; 

      --Init borders
      IF   begin_year = '0' THEN
       RAISE NOTICE '***Init borders';
       first_flag := true ; --first time flag
       begin_year := current_year ;
       begin_month := current_month ;   
   
        IF current_month = '12' THEN
          next_year := date_part('year' ,rec_shipment_date."SHIPMENT_DATE" + interval '1 year') ;
        ELSE
          next_year := current_year ;
        END IF;
     
       next_month := date_part('month' ,rec_shipment_date."SHIPMENT_DATE" + interval '1 month') ;

      END IF;

--      RAISE NOTICE 'current_year=% , current_month=% ',current_year,current_month;
--      RAISE NOTICE 'begin_year=% , begin_month=% ',begin_year,begin_month;
--      RAISE NOTICE 'next_year=% , next_month=% ',next_year,next_month;

      -- Check current date into borders NOT for First time

      RAISE NOTICE 'Current data = %',to_char( to_date( current_year||'.'||current_month, 'YYYY.MM'), 'YYYY.MM');
      RAISE NOTICE 'Begin data = %',to_char( to_date( begin_year||'.'||begin_month, 'YYYY.MM'), 'YYYY.MM');
      RAISE NOTICE 'Next data = %',to_char( to_date( next_year||'.'||next_month, 'YYYY.MM'), 'YYYY.MM');

      IF to_date( current_year||'.'||current_month, 'YYYY.MM') >= to_date( begin_year||'.'||begin_month, 'YYYY.MM') AND 
         to_date( current_year||'.'||current_month, 'YYYY.MM') < to_date( next_year||'.'||next_month, 'YYYY.MM') AND 
         NOT first_flag 
      THEN
         RAISE NOTICE '***CONTINUE';
         CONTINUE ; 
      ELSE
       --NEW borders only for second and after time 
       RAISE NOTICE '***NEW BORDERS';
       begin_year := current_year ;
       begin_month := current_month ;   
   
        IF current_month = '12' THEN
          next_year := date_part('year' ,rec_shipment_date."SHIPMENT_DATE" + interval '1 year') ;
        ELSE
          next_year := current_year ;
        END IF;
     
       next_month := date_part('month' ,rec_shipment_date."SHIPMENT_DATE" + interval '1 month') ;


      END IF;      

      IF to_number(current_month,'99') < 10 THEN
        current_month := '0'||current_month ; 
      END IF ;

      IF to_number(begin_month,'99') < 10 THEN
        begin_month := '0'||begin_month ; 
      END IF ;

      IF to_number(next_month,'99') < 10 THEN
        next_month := '0'||next_month ; 
      END IF ;

      RAISE NOTICE 'current_year=% , current_month=% ',current_year,current_month;
      RAISE NOTICE 'begin_year=% , begin_month=% ',begin_year,begin_month;
      RAISE NOTICE 'next_year=% , next_month=% ',next_year,next_month;

      partition_name := 'data_'||begin_year||begin_month||'01_'||next_year||next_month||'01'  ;

      RAISE NOTICE 'PARTITION NUMBER % , TABLE NAME =%',i , partition_name;
      
      EXECUTE format('CREATE TABLE ' || quote_ident(partition_name) || ' PARTITION OF data FOR VALUES FROM ( %L ) TO ( %L )  ' , begin_year||'-'||begin_month||'-01' , next_year||'-'||next_month||'-01'  ) ; 

      index_name := partition_name||'_shipment_id_parameter_id_idx';
      RAISE NOTICE 'INDEX NAME =%',index_name;
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_ID", "PARAMETER_ID") TABLESPACE pg_default ' ) ; 

      index_name := partition_name||'_lasermark_idx';
      RAISE NOTICE 'INDEX NAME =%',index_name;
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("LASERMARK" COLLATE pg_catalog."default") TABLESPACE pg_default ' ) ; 

      index_name := partition_name||'_shipment_id_idx';
      RAISE NOTICE 'INDEX NAME =%',index_name;
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_ID") TABLESPACE pg_default ' ) ; 

      index_name := partition_name||'_parameter_id_idx';
      RAISE NOTICE 'INDEX NAME =%',index_name;
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("PARAMETER_ID") TABLESPACE pg_default ' ) ; 

      index_name := partition_name||'_shipment_date_idx';
      RAISE NOTICE 'INDEX NAME =%',index_name;
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_DATE") TABLESPACE pg_default ' ) ; 

      --Drop first time flag
      first_flag := false ;

  END LOOP;
end
$$;

Tagħbija d-dump maħluqa fil-pass 3.

pg_restore -h хост -юзер -d база --data-only --format=c --table=data --verbose  data.dmp > data_restore.log 2>&1

Oħloq taqsima separata għal data antika

---------------------------------------------------
--create_partition_for_old_dates.sql
--create partitions for keeping old dates 
--version 1.0
do language plpgsql $$
declare 
rec_shipment_date RECORD ;
partition_name varchar;
index_name varchar;

begin

      SELECT min("SHIPMENT_DATE") AS min_date INTO rec_shipment_date from data ;

      RAISE NOTICE 'Old date is %',rec_shipment_date.min_date ;

      partition_name := 'data_old_dates'  ;

      RAISE NOTICE 'PARTITION NAME IS %',partition_name;

      EXECUTE format('CREATE TABLE ' || quote_ident(partition_name) || ' PARTITION OF data FOR VALUES FROM ( %L ) TO ( %L )  ' , '1900-01-01' , 
              to_char( rec_shipment_date.min_date,'YYYY')||'-'||to_char(rec_shipment_date.min_date,'MM')||'-01'  ) ; 

      index_name := partition_name||'_shipment_id_parameter_id_idx';
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_ID", "PARAMETER_ID") TABLESPACE pg_default ' ) ; 

      index_name := partition_name||'_lasermark_idx';
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("LASERMARK" COLLATE pg_catalog."default") TABLESPACE pg_default ' ) ; 

      index_name := partition_name||'_shipment_id_idx';
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_ID") TABLESPACE pg_default ' ) ; 

      index_name := partition_name||'_parameter_id_idx';
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("PARAMETER_ID") TABLESPACE pg_default ' ) ; 

      index_name := partition_name||'_shipment_date_idx';
      EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_DATE") TABLESPACE pg_default ' ) ; 

end
$$;

Riżultati finali:

Kien
Spiża: 502 997.55
Ħin ta' eżekuzzjoni: 505 sekonda.

Sar
Spiża: 68 533.70
Ħin ta' eżekuzzjoni: 69 sekondi

Denja, pjuttost denja. U meta wieħed iqis li tul it-triq irnexxielna ftit jew wisq nikkontrollaw il-mekkaniżmu ta 'qsim f'PostgreSQL 10 - riżultat eċċellenti.

Digressjoni lirika

Huwa possibbli li tagħmel saħansitra aħjar - IVA, TISTA'!Biex tagħmel dan għandek bżonn tuża MATERIALIZED VIEW.
OĦLOQ VISTA MATERJALIZZATA LASERMARK_VIEW

CREATE MATERIALIZED VIEW LASERMARK_VIEW 
AS
SELECT w."LASERMARK" , MAX(s."SHIPMENT_DATE") AS "SHIPMENT_DATE"
FROM shipment s INNER JOIN data w ON s."SHIPMENT_ID" = w."SHIPMENT_ID" 
GROUP BY w."LASERMARK" ;

CREATE INDEX lasermark_vw_shipment_date_ind on lasermark_view USING btree ("SHIPMENT_DATE") TABLESPACE pg_default;
analyze lasermark_view ;

Għal darb'oħra nerġgħu niktbu t-talba:
Mistoqsija bl-użu ta 'dehra mmaterjalizzata

SELECT
            p."PARAMETER_ID" as  parameter_id,
            pc."PC_NAME" AS pc_name,
            pc."CUSTOMER_PARTNUMBER" AS customer_partnumber,
            w."LASERMARK" AS lasermark,
            w."LOTID" AS lotid,
            w."REPORTED_VALUE" AS reported_value,
            w."LOWER_SPEC_LIMIT" AS lower_spec_limit,
            w."UPPER_SPEC_LIMIT" AS upper_spec_limit,
            p."TYPE_CALCUL" AS type_calcul,
            s."SHIPMENT_NAME" AS shipment_name,
            s."SHIPMENT_DATE" AS shipment_date,
            extract(year from s."SHIPMENT_DATE") AS year,
            extract(month from s."SHIPMENT_DATE") as month,
            s."REPORT_NAME" AS report_name,
            p."STC_NAME" AS STC_name,
            p."CUSTOMERPARAM_NAME" AS customerparam_name
        FROM data w INNER JOIN shipment s ON s."SHIPMENT_ID" = w."SHIPMENT_ID"
             INNER JOIN parameters p ON p."PARAMETER_ID" = w."PARAMETER_ID"
             INNER JOIN shipment_pc sp ON s."SHIPMENT_ID" = sp."SHIPMENT_ID"
             INNER JOIN pc pc ON pc."PC_ID" = sp."PC_ID"
             INNER JOIN LASERMARK_VIEW md ON md."SHIPMENT_DATE" = s."SHIPMENT_DATE" AND md."LASERMARK" = w."LASERMARK"
        WHERE 
              s."SHIPMENT_DATE" >= '2018-07-01' AND s."SHIPMENT_DATE" <= '2018-09-30';

U nġibu riżultat ieħor:
Kien
Spiża: 502 997.55
Ħin ta' eżekuzzjoni: 505 sekondi

Sar
Spiża: 42 481.16
Ħin ta' eżekuzzjoni: 43 sekondi.

Għalkemm, ovvjament, riżultat promettenti bħal dan huwa qarrieqi; l-ideat jeħtieġ li jiġu aggornati. Allura l-ħin totali biex tirċievi d-dejta mhux se jgħin ħafna. Iżda bħala esperiment huwa pjuttost interessanti.

Fil-fatt, kif irriżulta, grazzi mill-ġdid asmm u Habru!- Il-mistoqsija tista' titjieb aktar.

Wara kelma

Għalhekk, il-klijent huwa sodisfatt. U li jieħu vantaġġ mis-sitwazzjoni.

Kompitu ġdid: X'tista' toħroġ biex tapprofondixxi u tespandi?

U mbagħad niftakar - guys, m'għandniex monitoraġġ tad-databases PostgreSQL tagħna.

Idejn il-qalb, għad hemm xi monitoraġġ fil-forma ta 'Cloud Watch fuq AWS. Imma x'inhu l-benefiċċju ta' dan il-monitoraġġ għad-DBA? B'mod ġenerali, prattikament xejn.

Jekk għandek iċ-ċans li tagħmel xi ħaġa utli u interessanti għalik innifsek, ma tistax ma tieħu vantaġġ minn dan iċ-ċans...
GĦAL

Hekk niġu għall-aktar parti interessanti:

3 ta’ Diċembru 2018.
Tieħu deċiżjoni biex tibda r-riċerka dwar il-kapaċitajiet disponibbli għall-monitoraġġ tal-prestazzjoni tal-mistoqsijiet PostgreSQL.

Imma dik hija storja kompletament differenti.

Ser jitkompla aktar il-quddiem…

Sors: www.habr.com

Happy Party jew ftit linji ta 'memorji dwar kif issir taf il-qsim f'PostgreSQL10