Hierarhiskas datu struktūrasHierarhiskas attiecības starp darbiniekiem un vadītājiem

create table DARBINIEKI(D_NUM number Primary Key,D_UZV varchar2(10),VAD_NUM number);

begininsert into DARBINIEKI values(1, 'Sakne', NULL );insert into DARBINIEKI values (2, 'Zars', 1);insert into DARBINIEKI values (3, 'Celms', 2);insert into DARBINIEKI values (4, 'Lapa', 2);insert into DARBINIEKI values (5, 'Koks', 4);insert into DARBINIEKI values (6, 'Liepa', 4);insert into DARBINIEKI values (7, 'Ozols', 1);insert into DARBINIEKI values (8, 'Egle', 7);insert into DARBINIEKI values (9, 'Priede', 1);insert into DARBINIEKI values (10, 'Apse', 9);insert into DARBINIEKI values (11, 'Goba', 10);insert into DARBINIEKI values (12, 'Bumbiere', 9);insert into DARBINIEKI values (13, 'Atvase', NULL);insert into DARBINIEKI values (14, 'Roze', 13);insert into DARBINIEKI values (15, 'Cinis', 14);insert into DARBINIEKI values (16, 'Zirnis', 14);end;

1 Sakne 13 Atvase

2 Zars 7 Ozols 9 Priede 14 Roze

3 Celms 4 Lapa 8 EgleAtvase

10 Apse 12 Bumbiere

6 Liepa5 Koks 16 Zirnis 15 Cinis11 Goba

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Saknes mezglu atrašanaSELECT A.D_NUM, A.D_UZVFROM Darbinieki AWHERE A.VAD_NUM IS NULL;

D_NUM D_UZV--------------------------- 1 Sakne 13 Atvase

Vecāku mezglu atrašanaSELECT A.D_UZV Darbinieks, B.D_UZV VaditajsFROM Darbinieki A, Darbinieki BWHERE A.VAD_NUM = B.D_NUM;

DARBINIEKS VADITAJS----------------------------------------Priede SakneOzols SakneZars SakneLapa ZarsCelms Zars . . . Roze AtvaseZirnis RozeCinis Roze

Lapu mezglu atrašanaSELECT A.D_UZV Mezgli_lapasFROM Darbinieki AWHERE NOT EXISTS (SELECT D_NUM FROM Darbinieki B WHERE B.VAD_NUM = A.D_NUM);

MEZGLI_LAPAS--------------------------KoksEgle. . . Liepa

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Hierarhiskas struktūras elementi1. Mezgla punkts, mezgls (node).

2. Vecāka mezgla punkts (parent node).

3. Bērna mezgla punkts (child node).

4. Sakne (root).

5. Lapa (leaf).

6. Līmenis (level).

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Speciāla konstrukcija hierarhisko vaicājumu veidošanai

Lai vieglāk veidotu vaicājumus, kas saistīti ar hierarhiskām datu struktūrām, SQL

ir iekļautas speciālas struktūras un funkcijas:

1) START WITH – norāda apskatāmās hierarhijas sakni (-es);

2) CONNECT BY - nosaka saites starp vecāku un bērnu rakstiem;

3) PRIOR – aiz PRIOR uzreiz seko vecāku mezgla norāde (var būt vairāki);

4) LEVEL – hierarhijas līmeņa norāde.

Noteikumā “condition” var iekļaut apakšvaicājumu.

...PRIOR izteiksme = izteiksme (var izmantot ne tikai =)vai ...izteiksme = PRIOR izteiksme

CONNECT_BY_ROOT – izvada saknes elementuCONNECT_BY_ISLEAF – 1, ja ir lapa, 0, ja nav lapaCONNECT_BY_ISCYCLE – 1, ja ir bērna element, 0, ja nav bērna lementaSYS_CONNECT_BY_PATH – izvada hierarhijuOrder SIBLING by – kārtība pēc vienu vecāku bērniem

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SQL hierarhisko paplašinājumu izmantošana

SELECT A.VAD_NUM Vad_numurs, A.D_UZV Darb_uzvards, A.D_NUM Darb_numurs FROM Darbinieki ASTART WITH A.D_NUM = 13 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM;

VAD_NUMURS DARB_UZVARDS DARB_NUMURS------------------------------------------------------------------------------------------- -- Atvase 13 13 Priede 9 13 Roze 14 9 Apse 10 9 Bumbiere 12 14 Cinis 15 14 Zirnis 16

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SELECT A.VAD_NUM Vad_numurs, A.D_UZV Darb_uzvards, A.D_NUM Darb_numurs FROM Darbinieki ASTART WITH A.D_NUM = 13 CONNECT BY PRIOR A.VAD_NUM = A.D_NUM;

VAD_NUMURS DARB_UZVARDS DARB_NUMURS---------------------------------------------------------------------------------- Atvase 13

SELECT A.D_UZV, LEVEL, SYS_CONNECT_BY_PATH(A.D_UZV, '/') HierarhijaFROM Darbinieki ASTART WITH A.D_NUM = 13 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM;

D_UZV LEVEL HIERARHIJA Atvase 1 /Atvase Priede 2 /Atvase/Priede Apse 3 /Atvase/Priede/Apse Goba 4 /Atvase/Priede/Apse/Goba Bumbiere 3 /Atvase/Priede/Bumbiere Roze 2 /Atvase/Roze Cinis 3 /Atvase/Roze/Cinis Zirnis 3 /Atvase/Roze/Zirnis

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Lapu noteikšana

SELECT A.D_UZV, connect_by_isleafFROM Darbinieki ASTART WITH A.D_NUM = 13 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM;

Noteikšana vai ir cikls

SELECT A.D_UZV, connect_by_cycleFROM Darbinieki ASTART WITH A.D_NUM = 13 CONNECT BY NOCYCLE PRIOR A.D_NUM = A.VAD_NUM;

Noteikšana vai ir cikls

SELECT A.D_UZV, LEVEL-1, connect_by_root A.VAD_NUMFROM Darbinieki ASTART WITH A.D_NUM = 13 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM;

11 Goba

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SELECT VAD_NUM Vad_numurs, A.D_UZV Darb_uzvards, A.D_NUM Darb_numursFROM Darbinieki ASTART WITH A.D_NUM = 13 CONNECT BY A.D_NUM = A.VAD_NUM;

VAD_NUMURS DARB_UZVARDS DARB_NUMURS-------------------------------------------------------------------------------------------- -- Atvase 13

SELECT VAD_NUM Vad_numurs, A.D_UZV Darb_uzvards, A.D_NUM Darb_numursFROM Darbinieki ASTART WITH A.D_NUM = 13 CONNECT BY A.VAD_NUM = A.D_NUM;

VAD_NUMURS DARB_UZVARDS DARB_NUMURS------------------------------------------------------------------------------------------- Atvase 13

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SELECT A.D_NUM, A.D_UZV, A.VAD_NUM, LEVELFROM Darbinieki ASTART WITH A.D_NUM = 1 CONNECT BY PRIOR A.D_NUM = A.VAD_NUMORDER BY LEVEL;

D_NUM D_UZV VAD_NUM LEVEL---------------------------------------------------------------- 1 Sakne 1 2 Zars 1 2 7 Ozols 1 2 9 Priede 1 2 3 Celms 2 3 10 Apse 9 3 12 Bumbiere 9 3 8 Egle 7 3 4 Lapa 2 3 5 Koks 4 4 11 Goba 10 4 6 Liepa 4 4

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SELECT A.D_NUM, A.D_UZV, A.VAD_NUM, LEVELFROM Darbinieki AWHERE LEVEL = 2START WITH A.D_NUM = 1 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM;

D_NUM D_UZV VAD_NUM LEVEL------------------------------------------------------------------ 2 Zars 1 2 7 Ozols 1 2 9 Priede 1 2

SELECT COUNT(DISTINCT LEVEL) FROM Darbinieki A START WITH A.D_NUM = 1 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM; COUNT(DISTINCTLEVEL)---------------------------------------- 4

SELECT LEVEL, COUNT(A.D_NUM) FROM Darbinieki A START WITH A.D_NUM = 1 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM GROUP BY LEVEL; LEVEL COUNT(A.D_NUM)--------------------------------------- 1 1 2 3 3 5 4 3

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SELECT LEVEL, LPAD(‘ ‘, 2*(LEVEL -1)) || D_UZV Darbinieki, A.D_NUM, A.VAD_NUM FROM Darbinieki A START WITH A.D_NUM = 1 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM;

LEVEL DARBINIEKI D_NUM VAD_NUM--------------------------------------------------------------------------- 1 Sakne 1 2 Zars 2 1 3 Celms 3 2 3 Lapa 4 2 4 Koks 5 4 4 Liepa 6 4 2 Ozols 7 1 3 Egle 8 7 2 Priede 9 1 3 Apse 10 9 4 Goba 11 10 3 Bumbiere 12 9

SELECT A.D_NUM, A.D_UZV, A.VAD_NUM FROM Darbinieki A START WITH A.D_NUM = (SELECT B.D_NUM FROM Darbinieki B WHERE B.D_UZV = ‘Lapa’) CONNECT BY PRIOR A.D_NUM = A.VAD_NUM;

D_NUM D_UZV VAD_NUM------------------------------------------------- 4 Lapa 2 5 Koks 4 6 Liepa 4

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SELECT A.D_NUM, A.D_UZV, A.VAD_NUM FROM Darbinieki A WHERE A.D_UZV = ‘Lapa’ START WITH A.D_NUM = 2 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM;

D_NUM D_UZV VAD_NUM------------------------------------------------------ 4 Lapa 2

SELECT SUM(A.D_NUM) FROM Darbinieki A START WITH A.D_NUM = 2 CONNECT BY PRIOR A.D_NUM = A.VAD_NUM;

SUM(A.D_NUM)-------------------------- 20 (2 + 3 + 4+ 5 + 6)

SELECT A.D_NUM, A.D_UZV, A.VAD_NUM FROM Darbinieki A WHERE LEVEL = 1 START WITH A.VAD_NUM IS NULL CONNECT BY A.VAD_NUM = PRIOR A.D_NUM;

D_NUM D_UZV VAD_NUM------------------------------------------------------- 1 Sakne 13 Atvase

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create table DARBINIEKI(DA_NUM number Primary key,DA_UZV varchar2(20),ALGA number(8,2),DE_NUM number,VADIT_NU number);

insert into DARBINIEKI values(1, 'Sakne', 900,1,NULL);insert into DARBINIEKI values(2, 'Zars', 800,1,1);insert into DARBINIEKI values(3, 'Stumrs', 800,1,1);insert into DARBINIEKI values(4, 'Sakne', 600,1,2);insert into DARBINIEKI values(5, 'Lapa', 600,1,2);insert into DARBINIEKI values(6, 'Ozols', 800,2,1);insert into DARBINIEKI values(7, 'Osis', 700,2,6);insert into DARBINIEKI values(8, 'Alksnis', 700,2,6);insert into DARBINIEKI values(9, 'Egle', 700,2,8);insert into DARBINIEKI values(10, 'Priede', 800,3,1);insert into DARBINIEKI values(11, 'Virsis', 700,3,10);insert into DARBINIEKI values(12, 'Persiks', 600,3,11);

create table DEPARTAMENTI(DE_NUM number Primary key,DE_NOS varchar2(20));

insert into DEPARTAMENTI values(1, 'DEP1');insert into DEPARTAMENTI values(2, 'DEP2');insert into DEPARTAMENTI values(3, 'DEP3');

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Darbinieku pakārtotības koks

1 DEP_1

2 DEP_1 3 DEP_1

4 DEP_1 5 DEP_1

6 DEP_2 10 DEP_3

9 DEP_2

8 DEP_27 DEP_2

12 DEP_3

11 DEP_3

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Departamentu darbinieku algu summa un vidējā visu departamentu darbinieku algu summa

select 'AVG ', 0 DE_KOPĀ, AVG(c.DE_KOPĀ)from (select b.DE_NOS, SUM(a.ALGA) DE_KOPĀ from DARBINIEKI a, DEPARTAMENTI b where a.DE_NUM = b.DE_NUM group by b.DE_NOS) cUNION ALLselect e.DE_NOS, SUM(d.ALGA) DE_KOPĀ, 0 from DARBINIEKI d, DEPARTAMENTI e where d.DE_NUM = e.DE_NUM group by e.DE_NOS;

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Pakārtotais vaicājums ar starpniecību (subquery factoring statement)

WITH DE_IZMAKSAS as ( select DE_NOS, SUM(ALGA) DE_KOPĀ from DARBINIEKI a, DEPARTAMENTI b where a.DE_NUM = b.DE_NUM group by DE_NOS), VID_IZMAKSAS as ( select SUM(DE_KOPĀ)/COUNT(*) VID from DE_IZMAKSAS)

select * from DE_IZMAKSASwhere DE_KOPĀ>= (select VID from VID_IZMAKSAS) order by DE_NOS;

Departamenta nosaukums un darbinieku algu summa.

Vidējā departamentu darbinieku algu summa.

Departamenti, kuru darbinieku algu summa ir lielāka vai vienāda ar vidējo departamentu darbinieku algu summu

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Rekursīvs vaicājums ar starpniecību(recursive subquery factoring )

Noteikt darbiniekus, kuri tieši vai netieši sniedz pārskatus 1 darbiniekam un viņu atskaišu līmeni.The following statement shows the employees who directly or indirectly report to employee 1 and their reporting level.

WITH ATSK_1 (NUM, UZV, VADIT, ATS_LIM) AS (select DA_NUM, DA_UZV, VADIT_NU, 0 ATS_LIM from DARBINIEKI where DA_NUM = 1 UNION ALL select e.DA_NUM, e.DA_UZV, e.VADIT_NU, ATS_LIM+1 from ATSK_1 r, DARBINIEKI e where r.NUM = e.VADIT_NU )

select NUM, UZV, VADIT, ATS_LIMfrom ATSK_1order by ATS_LIM, NUM;

D_NUM=101NUM=101 VAD_ID=100 0r.NUM=101 e.VAD_ID=108 1r.NUM=101 e.VAD_ID=200 1r.NUM=101 e.VAD_ID=203 1r.NUM=101 e.VAD_ID=204 1r.NUM=101 e.VAD_ID=205 1

r.NUM=108 e.VAD_ID=109 2r.NUM=108 e.VAD_ID=110 2r.NUM=108 e.VAD_ID=111 2r.NUM=205 e.VAD_ID=206 2

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The following statement shows employees who directly or indirectly report to employee 1, their reporting level, and their management chain.

with ATSK_1 (NUM, UZV, VADIT, ATS_LIM, VAD_SAR) AS (select DA_NUM, DA_UZV, VADIT_NU, 0 ATS_LIM, CAST(VADIT_NU as varchar2(200)) from DARBINIEKI where DA_NUM= 1 UNION ALL select e.DA_NUM, e.DA_UZV, e.VADIT_NU, ATS_LIM+1, CAST(VAD_SAR || ',' || VADIT_NU as varchar2(200)) FROM ATSK_1 r, DARBINIEKI e WHERE r.NUM = e.VADIT_NU )

select NUM, UZV, VADIT, ATS_LIM, VAD_SARfrom ATSK_1order by ATS_LIM, NUM;

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The following statement shows the employees who directly or indirectly report to employee 1 and their reporting level. It stops at reporting level 1.

with ATSK_1 (NUM, UZV, VADIT, ATS_LIM, VAD_SAR) AS (select DA_NUM, DA_UZV, VADIT_NU, 0 ATS_LIM, CAST(VADIT_NU as varchar2(200)) from DARBINIEKI where DA_NUM= 1 UNION ALL select e.DA_NUM, e.DA_UZV, e.VADIT_NU, ATS_LIM+1, CAST(VAD_SAR || ',' || VADIT_NU as varchar2(200)) FROM ATSK_1 r, DARBINIEKI e WHERE r.NUM = e.VADIT_NU )select NUM, UZV, VADIT, ATS_LIM, VAD_SARfrom ATSK_1where ATS_LIM <=1order by ATS_LIM, NUM;

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The following statement shows the entire organization, indenting for each level of management.

with POZ_IZV (NUM, UZV, VADIT, ATS_LIM, ALGA) as (select DA_NUM, DA_UZV, VADIT_NU, 0 ATS_LIM, ALGA from DARBINIEKI where VADIT_NU is null UNION ALL SELECT e.DA_NUM, e.DA_UZV, e.VADIT_NU, r.ATS_LIM+1 ATS_LIM, e.ALGA from POZ_IZV r, DARBINIEKI e WHERE r.NUM = e.VADIT_NU) SEARCH DEPTH FIRST BY UZV SET order1select LPAD(' ',2*ATS_LIM)||UZV uzvārds, NUM, VADIT, ALGAfrom POZ_IZVorder by order1;

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The following statement shows the entire organization, indenting for each level of management, with each level ordered by hire_date. The value of is_cycle is set to Y for any employee who has the same hire_date as any manager above him in the management chain.

WITH dup_hiredate (eid, emp_last, mgr_id, reportLevel, hire_date, job_id) AS ( SELECT employee_id, last_name, manager_id, 0 reportLevel, hire_date, job_id FROM employees WHERE manager_id is null UNION ALL SELECT e.employee_id, e.last_name, e.manager_id, r.reportLevel+1 reportLevel, e.hire_date, e.job_id FROM dup_hiredate r, employees e WHERE r.eid = e.manager_id ) SEARCH DEPTH FIRST BY hire_date SET order1 CYCLE hire_date SET is_cycle TO 'Y' DEFAULT 'N'SELECT lpad(' ',2*reportLevel)||emp_last emp_name, eid, mgr_id, hire_date, job_id, is_cycleFROM dup_hiredateORDER BY order1;

EMP_NAME EID MGR_ID HIRE_DATE JOB_ID IS_CYCLE-------------------- ---------- ---------- --------- ---------- --------King 100 17-JUN-03 AD_PRES N De Haan 102 100 13-JAN-01 AD_VP N Hunold 103 102 03-JAN-06 IT_PROG N Austin 105 103 25-JUN-05 IT_PROG N. . . Kochhar 101 100 21-SEP-05 AD_VP N Mavris 203 101 07-JUN-02 HR_REP N Baer 204 101 07-JUN-02 PR_REP N

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Higgins 205 101 07-JUN-02 AC_MGR N Gietz 206 205 07-JUN-02 AC_ACCOUNT Y Greenberg 108 101 17-AUG-02 FI_MGR N Faviet 109 108 16-AUG-02 FI_ACCOUNT N Chen 110 108 28-SEP-05 FI_ACCOUNT N. . .

The following statement counts the number of employees under each manager.

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The following statement counts the number of employees under each manager.

WITH emp_count (eid, emp_last, mgr_id, mgrLevel, salary, cnt_employees) AS ( SELECT employee_id, last_name, manager_id, 0 mgrLevel, salary, 0 cnt_employees FROM employees UNION ALL SELECT e.employee_id, e.last_name, e.manager_id, r.mgrLevel+1 mgrLevel, e.salary, 1 cnt_employees FROM emp_count r, employees e WHERE e.employee_id = r.mgr_id ) SEARCH DEPTH FIRST BY emp_last SET order1SELECT emp_last, eid, mgr_id, salary, sum(cnt_employees), max(mgrLevel) mgrLevelFROM emp_countGROUP BY emp_last, eid, mgr_id, salaryHAVING max(mgrLevel) > 0ORDER BY mgr_id NULLS FIRST, emp_last;

EMP_LAST EID MGR_ID SALARY SUM(CNT_EMPLOYEES) MGRLEVEL------------------ ---------- ---------- ---------- ------------------ ----------King 100 24000 106 3Cambrault 148 100 11000 7 2De Haan 102 100 17000 5 2Errazuriz 147 100 12000 6 1Fripp 121 100 8200 8 1Hartstein 201 100 13000 1 1Kaufling 122 100 7900 8 1. . .

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