1. The Model Clause A case study at E.On

2. Introduction 2 Oliver.Hayden@eon.com A little about me, the company I work for, the team I work in and today’s presentation.

3. A brief introduction to the model clause Example statement: 3 http://docs.oracle.com/cd/B28359_01/server.111/b28313/sqlmodel.htm select empno, ename, sal from emp where deptno = 10 MODEL dimension by (empno) measures (ename, sal) rules () /

4. 4 The constraints We must patch the primary and the standby at the same time The primary and standby have the same sid, but are on different servers Databases at the same Oracle version on the same server share the same Oracle home What we have to work with An up to date table in an Oracle database, containing a record of every database in our estate, recording sid, hostname, database role (either primary or standby) and oracle version The model clause Scenario 1: Quarterly Critical Patch Updates

5. Clump A orcl1 orcl5 orcl1 orcl2 orcl2 orcl3 orcl4 orcl4 orcl5 5 Clump B orcl6 orcl7 orcl7 Clump C orcl8 SIDPrimary host Standby host orcl1box1box3 orcl2box3box4 orcl3box4none orcl4box4box5 orcl5box2box1 orcl6box6none orcl7box7box6 orcl8box8none

6. 6 create table lod (sid varchar2(20), host varchar2(20), dbrole varchar2(10)); insert into lod values ('orcl1','box1','prmy'); insert into lod values ('orcl1','box3','stby'); insert into lod values ('orcl2','box3','prmy'); insert into lod values ('orcl2','box4','stby'); insert into lod values ('orcl3','box4','prmy'); insert into lod values ('orcl4','box4','stby'); insert into lod values ('orcl4','box5','prmy'); insert into lod values ('orcl5','box2','prmy'); insert into lod values ('orcl5','box1','stby'); insert into lod values ('orcl6','box6','prmy'); insert into lod values ('orcl7','box7','prmy'); insert into lod values ('orcl7','box6','stby'); insert into lod values ('orcl8','box8','prmy'); commit; var n number begin select count(*) into :n from lod; end; /

7. 7 select clump, sid, host, dbrole, rn from lod model dimension by (sid, host, dbrole) measures (rownum as clump,rownum as rn) rules iterate(10000) until (iteration_number =:n) ( --update clumps for the hosts to the lowest value currently for identical hosts clump[any,host,any]= least ( nvl(min(clump) over (partition by host order by clump rows between unbounded preceding and unbounded following),:n) ), --update clump for the sids to be the lowest of current clump values clump[any,host,any]= least ( nvl(min(clump) over (partition by sid order by clump rows between unbounded preceding and unbounded following),:n) ) /

8. 8 Intermediate step.

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10. 10 Intermediate step.

11. 11 Final output.

12. 12 alter table lod add (version varchar2(20) default '10g'); update lod set version ='11g' where sid = 'orcl2'; commit; The previous example was simplified, here we also take into account Oracle version

13. 13 select version, clump, sid, host, dbrole, rn from lod MODEL partition by (version) dimension by (sid, host, dbrole) measures (rownum as clump,rownum as rn) rules iterate(10000) until (iteration_number =:n) ( --update clumps for the hosts to the lowest value currently for identical hosts clump[any,host,any]= least ( nvl(min(clump) over (partition by host order by clump rows between unbounded preceding and unbounded following),:n) ), --update clump for the sids to be the lowest of current clump values clump[any,host,any]= least ( nvl(min(clump) over (partition by sid order by clump rows between unbounded preceding and unbounded following),:n) ) order by clump /

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15. Scenario 2: Missing data in a time-series 15 Original requirement arose during a project to investigate whether objects are being used.

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17. 17 desc dbm_apps.monitor_usage_aud@gfcspw01

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20. 20 with data as (select day as orig_day, value,day start_dt, nvl(lag(day) over (order by day desc nulls last),day)-1 end_dt from (select trunc(datefield) as day, count(*) as value from dbm_apps.monitor_usage_aud@gfcspw01 group by trunc(datefield)) order by day ) select value as quantity,s2 as time_period from data MODEL partition by (orig_day, start_dt, end_dt) dimension by (0 as z) measures (1 x,value, start_dt s2, end_dt e2) rules sequential order iterate (5) until ( previous(s2[ITERATION_NUMBER]) >= previous(e2[ITERATION_NUMBER]) ) ( x[ITERATION_NUMBER]=ITERATION_NUMBER,s2[ITERATION_NUMBER]=cv(start_dt)+ITERATION_NUMBER,e2[ITERATION_NUMBER]=cv(end_dt) ) order by s2, value

21. Scenario 3: team rota 21 There is a need for our team assignments to be easily visible to both ourselves and our customers. We also need to make sure that resource has been assigned.

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25. 25 create table pp_rota (DUTY VARCHAR2(20),PERSON NOT NULL VARCHAR2(20),WHEN DATE) /

26. 26 select when, duty||'.'||person, duty, decode(person,'MISSING',null,person) as real_person from pp_rota model partition by (when) dimension by (duty) measures (person) rules ( person['livebuild']=nvl(person[cv(duty)],'MISSING'),person['backflush']=nvl(person[cv(duty)],'MISSING'),person['systest']=nvl(person[cv(duty)],'MISSING'),person['ep']=nvl(person[cv(duty)],'MISSING') ) order by when, duty

27. Wrap up... 27