Prefas oswa ki jan lide nan seksyon te rive
Istwa a kòmanse isit la: Apre prèske tout resous yo pou optimize demann lan, nan tan sa a, yo te fin itilize, kesyon an leve - ki sa ki pwochen? Sa a se ki jan lide nan patisyon leve.
Digresyon lirik:
Jisteman 'nan moman sa a', paske . Mèsi ak Habru!
Se konsa, ki lòt fason ou ka fè kliyan an kontan, epi an menm tan amelyore konpetans pwòp ou a?
Pou senplifye tout bagay otank posib, Lè sa a, gen sèlman de fason radikalman amelyore yon bagay nan pèfòmans nan baz done a:
1) Chemen vaste - nou ogmante resous, chanje konfigirasyon an;
2) D' entansif - requête optimisation
Depi, mwen repete, nan moman sa a li pa t klè ankò ki lòt bagay yo chanje nan demann lan pi vit, yo te chwazi chemen an - chanjman konsepsyon tab la.
Se konsa, kesyon prensipal la rive: ki sa ak ki jan nou pral chanje?
Kondisyon inisyal yo
Premyèman, gen ERD sa a (yo montre nan yon fason senplifye kondisyonèl):
Karakteristik kle:
- relasyon anpil-a-anpil
- tab la deja gen yon kle patisyon potansyèl
Demann orijinal:
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' ;
Rezilta egzekisyon sou baz done tès la:
Koute : 502 997.55
Tan ekzekisyon: 505 segonn.
Kisa nou wè? Yon demann regilye, ki baze sou yon tranch tan.
Ann fè sipozisyon ki pi senp ki lojik: si gen yon echantiyon nan yon tranch tan, èske l ap ede nou? Sa a dwat - patisyon.
Ki sa ki seksyon?
Nan premye gade, chwa a se evidan - patisyon deklaratif nan tab la "chajman" lè l sèvi avèk kle "SHIPMENT_DATE" (sote twò lwen devan - nan fen a li te tounen soti yon ti kras mal nan pwodiksyon an).
Ki jan yo patisyon?
Kesyon sa a tou pa twò difisil. Erezman, nan PostgreSQL 10, gen kounye a yon mekanis patisyon imen.
Se konsa,:
- Sove yon pil fatra nan tab sous la - pg_dump source_table
- Efase tab orijinal la - gout tab source_table
- Kreye yon tab paran ak patisyon ranje - kreye tab source_table
- Kreye seksyon - kreye tab source_table, kreye endèks
- Enpòte pil fatra ki te kreye nan etap 1 - pg_restore
Scripts pou patisyon
Pou senplisite ak konvenyans, etap 2,3,4 yo te konbine nan yon sèl script.
Se konsa,:
Sove yon pil fatra nan tab sous la
pg_dump postgres --file=/dump/shipment.dmp --format=c --table=shipment --verbose > /dump/shipment.log 2>&1Efase tab sous la + Kreye yon tab paran ak patisyon ranje + Kreye patisyon
--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
$$;Enpòte pil fatra a
pg_restore -d postgres --data-only --format=c --table=shipment --verbose shipment.dmp > /tmp/data_dump/shipment_restore.log 2>&1Tcheke rezilta patisyon yo
Ki sa nou genyen kòm rezilta? Tèks konplè plan ekzekisyon an se gwo ak raz, kidonk li se byen posib limite tèt ou nan nimewo final yo.
Te
Pri: 502 997.55
Tan ekzekisyon: 505 segonn.
Te vin
Pri: 77 872.36
Tan ekzekisyon: 79 segonn.
Byen yon bon rezilta. Pri redwi ak tan ekzekisyon. Kidonk, itilizasyon partitioning bay efè a espere epi, an jeneral, pa gen sipriz.
Fè kliyan an kontan
Rezilta tès yo te prezante bay kliyan an pou revize. Epi apre yo fin revize li, yo te ba yo yon vèdik yon ti jan inatandi: "Bon, separe tab "done" la."
Wi, men nou te egzamine yon tab "shipment" konplètman diferan; tablo "done" pa gen jaden "SHIPMENT_DATE".
Pa gen pwoblèm, ajoute, chanje. Bagay pwensipal lan se ke kliyan an satisfè ak rezilta a, detay aplikasyon yo pa patikilyèman enpòtan.
Seksyon "done" tab prensipal la
An jeneral, pa gen okenn difikilte patikilye leve. Malgre ke, algorithm nan patisyon, nan kou, te chanje yon ti jan.
Ajoute kolòn "SHIPMENT_DATA" nan tablo "done".
psql -h хост -U база -d юзер
=> ALTER TABLE data ADD COLUMN "SHIPMENT_DATE" timestamp without time zone ;Ranpli valè kolòn "SHIPMENT_DATA" nan tablo "done" ak valè kolòn ki gen menm non ki soti nan tablo "shipment" la.
-----------------------------
--update_data.sql
--updating for altered table "data" to values of "shipment_data" from the table "shipment"
--version 1.0
do language plpgsql $$
declare
rec_shipment_data RECORD ;
shipment_date timestamp without time zone ;
row_count integer ;
total_rows integer ;
begin
select count(*) into total_rows from shipment ;
RAISE NOTICE 'Total %',total_rows;
row_count:= 0 ;
FOR rec_shipment_data IN SELECT * FROM shipment LOOP
update data set "SHIPMENT_DATE" = rec_shipment_data."SHIPMENT_DATE" where "SHIPMENT_ID" = rec_shipment_data."SHIPMENT_ID";
row_count:= row_count +1 ;
RAISE NOTICE 'row count = % , from %',row_count,total_rows;
END LOOP;
end
$$;Sove yon pil fatra nan "done" tab la
pg_dump postgres --file=/dump/data.dmp --format=c --table=data --verbose > /dump/data.log 2>&1</sourceRekreye "done" tab ki divize an
--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
$$;
Chaje pil fatra ki te kreye nan etap 3.
pg_restore -h хост -юзер -d база --data-only --format=c --table=data --verbose data.dmp > data_restore.log 2>&1Kreye yon seksyon separe pou ansyen done
---------------------------------------------------
--create_partition_for_old_dates.sql
--create partitions for keeping old dates
--version 1.0
do language plpgsql $$
declare
rec_shipment_date RECORD ;
partition_name varchar;
index_name varchar;
begin
SELECT min("SHIPMENT_DATE") AS min_date INTO rec_shipment_date from data ;
RAISE NOTICE 'Old date is %',rec_shipment_date.min_date ;
partition_name := 'data_old_dates' ;
RAISE NOTICE 'PARTITION NAME IS %',partition_name;
EXECUTE format('CREATE TABLE ' || quote_ident(partition_name) || ' PARTITION OF data FOR VALUES FROM ( %L ) TO ( %L ) ' , '1900-01-01' ,
to_char( rec_shipment_date.min_date,'YYYY')||'-'||to_char(rec_shipment_date.min_date,'MM')||'-01' ) ;
index_name := partition_name||'_shipment_id_parameter_id_idx';
EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_ID", "PARAMETER_ID") TABLESPACE pg_default ' ) ;
index_name := partition_name||'_lasermark_idx';
EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("LASERMARK" COLLATE pg_catalog."default") TABLESPACE pg_default ' ) ;
index_name := partition_name||'_shipment_id_idx';
EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_ID") TABLESPACE pg_default ' ) ;
index_name := partition_name||'_parameter_id_idx';
EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("PARAMETER_ID") TABLESPACE pg_default ' ) ;
index_name := partition_name||'_shipment_date_idx';
EXECUTE format('CREATE INDEX ' || quote_ident(index_name) || ' ON '|| quote_ident(partition_name) ||' USING btree ("SHIPMENT_DATE") TABLESPACE pg_default ' ) ;
end
$$;Rezilta final:
Te
Pri: 502 997.55
Tan ekzekisyon: 505 segonn.
Te vin
Pri: 68 533.70
Tan ekzekisyon: 69 segonn
Diy, byen merite. Epi konsidere ke sou wout la nou jere plis oswa mwens metrize mekanis nan patisyon nan PostgreSQL 10 - yon rezilta ekselan.
Degresyon lirik
Èske li posib fè menm pi byen - WI, OU KA!Pou fè sa ou bezwen sèvi ak MATERIALIZED VIEW.
KREYE VIEW MATERIALIZE 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 ;
Yon fwa ankò nou reekri demann lan:
Rekèt lè l sèvi avèk View materyalize
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';
Epi nou jwenn yon lòt rezilta:
Te
Pri: 502 997.55
Tan ekzekisyon: 505 segonn
Te vin
Pri: 42 481.16
Tan ekzekisyon: 43 segonn.
Malgre ke, nan kou, yon rezilta pwomèt konsa se twonpe, lide yo bezwen rafrechi. Se konsa, tan total pou resevwa done pa pral ede anpil. Men, kòm yon eksperyans li se byen enteresan.
Aktyèlman, jan li te tounen soti, mèsi ankò ak Habru!-
Apreword
Se konsa, kliyan an satisfè. AK bezwen pwofite sitiyasyon an.
Nouvo travay: Kisa ou ka vini ak apwofondi ak elaji?
Apre sa, mwen sonje - mesye, nou pa gen siveyans nan baz done PostgreSQL nou yo.
Men sou kè, toujou gen kèk siveyans nan fòm Cloud Watch sou AWS. Men, ki benefis siveyans sa a genyen pou DBA a? An jeneral, pratikman okenn.
Si ou gen yon chans fè yon bagay itil ak enteresan pou tèt ou, ou pa ka pa pwofite chans sa a...
POU
Men ki jan nou rive nan pati ki pi enteresan an:
3 desanm 2018.
Pran yon desizyon pou kòmanse rechèch sou kapasite ki disponib pou kontwole pèfòmans demann PostgreSQL.
Men, sa se yon istwa konplètman diferan.
A kontinye…
Sous: www.habr.com