Sesa t ed

1
6

• S?es?a?? ???t??? ?ed?µ????

• ??sa???? ?as???? ?????e?
• ??e?d??
• ?e?????sµ?? a?e?a??t?ta?
• ?etat??p? µ??t???? ?S se s?es?a?? µ??t???

2

?ef??a?? 6 S?es?a?? ???t???
?as???? ?????e?

• ?? s?es?a?? (relational) µ??t??? ded?µ????
  p??t????e ap? t?? Codd t? 1970.
• ? ?st????? e??as?a t?? Codd e??a? d?a??s?µ? st?
  d?e????s? http//www.acm.org/classics/nov95/toc.ht
  ml
• ? ap?? ?a? ?ata???t? d?µ? t?? e??a? d?? ap? ta
  a?t?a t?? te??st?a? ap???s?? t?? µ??t???? se
  ??as???? ?a? s??????e? efa?µ???? ??????
  apa?t?se??.
• ?? µe???? p?e????t?µa t?? µ??t???? e??a? ?t?
  µp??e? ?a pe????afe? µa??µat??? µe t? ß???e?a t??
  Te???a? S?????? (set theory) ? t??
  ?at?????µat???? ??????? (predicate logic).
• ??a ta eµp????? S??? ?p?st??????? t? s?es?a??
  µ??t??? ded?µ???? ? epe?t?se?? t??.

3

?ef??a?? 6 S?es?a?? ???t???
4

?ef??a?? 6 S?es?a?? ???t???
5

?ef??a?? 6 S?es?a?? ???t???
6

?ef??a?? 6 S?es?a?? ???t???
?as???? ?????e?

• ?as???? st???? t?? s?es?a??? µ??t???? e??a? ??
  e???
• ? ?p?st????? a?e?a?t?s?a? ded?µ????, ?ts? ?ste
  a??a??? st? f?s??? d?µ? ?a? ??????s? t?? ?? ?a
  µ?? apa?t??? a??a??? sta p?????µµata efa?µ????,
• ? ap?f??? t?? p?e??asµ?? ded?µ????, ? ?p????
  eµfa???eta? ?ta? ta ?d?a ded?µ??a ap????e???ta?
  p????? f???? se d?af??et???? pe?????? t?? ??,
• ? d?at???s? t?? a?e?a??t?ta? ?a? t?? s???pe?a?
  t?? ded?µ????,
• ? ?p?st????? t?? a??pt???? ???ss?? DDL-DML, ??
  ?p??e? st??????ta? st? ?e???a s??????, ?a?
  d?e?-???????? t? d?at?p?s? e??t?µ?t?? p??? t?
  S???.

7

?ef??a?? 6 S?es?a?? ???t???
?a ???ta S?st?µata

• H a??pt??? ?a? ? ???p???s? t?? ?fe??eta? ??????
  se t?e?? a?e???t?te? e?e???t???? p??sp??e?e?
• System R IBM San Jose,
• INGRES (Interactive Graphics Retrieval System)
  Berkeley,
• PRTV (Peterlee Relational Test Vehicle) IBM UK.

8

?ef??a?? 6 S?es?a?? ???t???
?a ???ta S?st?µata

• ?a ßas??? ??µata p?? apas????sa? t?te t???
  e?e???t?? ?ta?
• ? a??pt??? µ?a? d?µ?µ???? ???ssa? DDL-DML µe t??
  ???µas?a SQL (Structured Query Language),
• ? a??pt??? µ?a ?e???a? ??a t?? s??a?t?s?a???
  e?a?t?se??,
• ? a??pt??? ap?te?esµat???? µe??d?? ??a t?
  ße?t?st?p???s? e??t?µ?t??.

9

?ef??a?? 6 S?es?a?? ???t???
?a ???ta S?st?µata

• ?a p??ta eµp????? d?a??s?µa S??? p?? st???????a?
  st? s?es?a?? µ??t??? ded?µ????, eµfa??s???a? st?
  de?aet?a t?? 1970 ?a? 1980, ?p?? ta s?st?µata
• DB2 ?a? SQL/DS t?? eta??e?a? IBM, ?a?
• Oracle t?? eta??e?a? Oracle.
• ?p? t?? ?µ?da t?? INGRES p??????a? d?? eµp?????
  S???
• INGRES t?? eta??e?a? Relational Technologies,
• IDM (Intelligent Database Machine) t?? eta??e?a?
  Britton Lee.

10

?ef??a?? 6 S?es?a?? ???t???
Michael Stonebraker, Wikipedia
Stonebraker is a computer scientist specializing
in database research and development. His career
covers, and helped create, the majority of the
exi-sting relational database market today. He
is also the founder of Ingres, Illustra, Cohera
and StreamBase Systems, and was previously the
CTO of Informix. He is also an editor for the
book Readings in Database Systems. Stonebraker
earned his BSc degree from Princeton University
in 1965. From the University of Michigan, he
earned his MSc degree in 1967 and his PhD in
1971. He has received several awards, including
the IEEE John von Neumann Medal. Currently he is
teaching at MIT.
11

?ef??a?? 6 S?es?a?? ???t???
12

?ef??a?? 6 S?es?a?? ???t???
S??????a ?µp????? S?st?µata

• ?e???? ap? ta s??????a eµp????? d?a??s?µa S???
  p?? ?p?st??????? t? s?es?a?? µ??t??? e??a? ta
  e???
• SQL Server 2000 t?? Microsoft (http//www.microsof
  t.com)
• DB2 ?a? Informix t?? IBM (http//www.ibm.com)
• Oracle 10g t?? Oracle (http//www.oracle.com)
• Teradata t?? Teradata (http//www.teradata.com)

13

?ef??a?? 6 S?es?a?? ???t???
???a?e? (S??se??)

• ??a ?? ap?te?e?ta? ap? ??a s????? s??se??.
• ???e s??s? pa??stata? µe ??a? p??a?a (a??e??).
• ???e ??aµµ? µ?a? s??s?? ?a?e?ta? p?e??da (tuple)
  ?a? pa??st? µ?a e???af?.
• ???e st??? µ?a? s??s?? ap?te?e? ??a
  ?a?a?t???st??? (attribute) t?? e???af??.
• ?? p????? t?? ?a?a?t???st???? µ?a? s??s?? ???eta?
  ßa?µ?? (degree), e?? t? p????? t?? p?e??d??
  ???eta? p??????t?ta (cardinality).
• ???e ?a?a?t???st??? ??e? ??a s????? ep?t?ept??
  t?µ??, t? ped?? ???sµ?? (domain) t??
  ?a?a?t???st????.

14

?ef??a?? 6 S?es?a?? ???t???
S??µa ?a? St??µ??t?p?

• S??µa s??s?? S??d??µ?t??(??d????,???µa,t???f???,d?
  e????s?,???)

15

?ef??a?? 6 S?es?a?? ???t???
?d??t?te? S??se??

• ???e s??s? ??e? µ??ad??? ???µa µeta?? t?? s??se??
  t?? ??.
• ???e ?a?a?t???st??? ??e? µ??ad??? ???µa µ?sa st?
  s??s?. ?p?t??peta? d?? ?a?a?t???st???
  d?af??et???? s??se?? ?a ????? ?d?? ???µa.
• ? t?µ? e??? ?a?a?t???st???? e??a? at?µ???. ?
  t?µ?? e??? ?a?a?t???st???? a?????? st? ?d?? ped??
  ???sµ??.
• ?e? pa??e? ???? ? se??? d???s?? t??
  ?a?a?t???st???? µ?a? s??s??, ??te ? se??? t??
  p?e??d?? st? s??s?. ?µ??, ? se??? ap????e?s?? t??
  ded?µ???? ep??e??e? t? ????? epe?e??as?a? ?a?
  ?aµß??eta? ?p???.
• ?e? ep?t??peta? 2 p?e??de? ?a ta?t????ta?
  (??at??).

16

?ef??a?? 6 S?es?a?? ???t???
?d??t?te? S??se??
17

?ef??a?? 6 S?es?a?? ???t???
??e?d?? s??se??

• ??a ?a?a?t???st??? (? s????? ?a?a?t???st????)
  e??? p??a?a ???eta? ??e?d? a? µp??e? ?a
  d?a?????e? t?? d?af??et???? ??aµµ?? t?? p??a?a.
• ?? ep??e??µe?? ??e?d? ?a?e?ta? p??te???
  (primary), e?? ta ?p????pa ?a????ta?
  de?te?e???ta (secondary) ? ?p???f?a (candidate)
  ? e?a??a?t??? (alternative).
• S???et? (composite) ?ta? apa?t???ta? pe??ss?te?a
  t?? e??? ?a?a?t???st??? ??a ?a s????s??? ??a
  ??e?d?.

18

?ef??a?? 6 S?es?a?? ???t???
?e?????sµ?? ??e?a??t?ta?

• ?? pe?????sµ?? a?e?a??t?ta? (integrity
  constraints) p??pe? ?a ?s????? p??ta ??a ???e
  st??µ??t?p? t?? ?? (se ???e s??s? t?? ??). ??te
  ??a st??µ??t?p? ???µ??eta? ?????? (valid).
• ?? pe?????sµ?? a?e?a??t?ta? epa???e???ta? ???e
  f??? p?? p?a?µat?p?????ta? a??a??? sta ded?µ??a
  (e?sa????, d?a??af?, e??µ???s?).
• ?? pe?????sµ?? a?e?a??t?ta? e??a?
• ?e??? t?µ?? (null values),
• ??e?a??t?ta ??t?t?t?? (entity integrity),
• ??e?a??t?ta a?af???? (referential integrity), ?a?
• S?µas????????? pe?????sµ?? (semantics).

19

?ef??a?? 6 S?es?a?? ???t???
?e?????sµ?? ??e?a??t?ta?

• ?e??? t?µ?? (NULL) ?ta? de? ????????µe t?? t?µ?
  e??? ?a?a?t???st???? ? ??a t? s???e???µ???
  ?a?a?t???st??? de? µp????µe ?a p??sd????s??µe
  ??p??a t?µ?.

20

?ef??a?? 6 S?es?a?? ???t???
?e?????sµ?? a?e?a??t?ta?

• ??e?a??t?ta ??t?t?t?? ???e ??aµµ? t?? p??a?a
  p??sd?????eta? µ??ad??? ap? t? p??te??? ??e?d?.

21

?ef??a?? 6 S?es?a?? ???t???
?e?????sµ?? a?e?a??t?ta?

• ??e?a??t?ta a?af???? ?? t? ??e?d? ? e??? p??a?a
  ? ap?te?e? ?a?a?t???st??? e??? ????? p??a?a ?,
  t?te t? ? ap?te?e? ???? ??e?d? (foreign key) ??a
  t?? p??a?a ?.

22

?ef??a?? 6 S?es?a?? ???t???
?e?????sµ?? ??e?a??t?ta?

• S?µas????????? pe?????sµ?? ?p??ad?p?te s??????
  ?????µe ?a ??a??p??e?ta? ap? ta ap????e?µ??a
  ded?µ??a.
• p?. ?????a gt 18, p???p??es?a gt 5 ?t?.

23

?ef??a?? 6 S?es?a?? ???t???
?e?????sµ?? ??e?a??t?ta?

• ?? pe?????sµ?? a?e?a??t?ta? e??????ta?
• p??? t?? e?sa???? ded?µ????,
• p??? t? d?a??af? ded?µ????, ?a?
• p??? t?? e??µ???s? ded?µ????.
• ?? pa?aß???eta? ??p???? pe?????sµ??, t?te ?
  ?e?t?????a de? ???eta? ap?de?t?.

24

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???

• G?a ???e s????? ??t?t?t?? ?a? ???e s?????
  s?s?et?-se?? µp??e? ?a d?µ???????e? ??a? p??a?a?
  (s?????? µe ?d?? ???µa). ? p??a?a? ??e? ?? st??e?
  ta ?a?a?t?-??st??? t?? ???e s?????? ?a? ??e?d? t?
  a?t?st???? ??e?d? t?? ???e s??????.

25

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???

• ? p??????µe?? p??tas? e??a? ep?t?de?
  ap???ste?t???.
• ???pe? ?a ??ß??µe ?p??? t? ßa?µ? t?? s?s??t?s??,
  t?? ?p???e?t???t?ta, ta ?a?a?t???st??? p???ap???
  t?µ??, t?? ad??aµe? ??t?t?te?, t? ?e???e?s?/
  e?e?d??e?s?, t? s?ss?µ?t?s? ??p.
• ?p???e? pe??pt?s? ? p????f???a ??a ??p??? s?????
  ??t?t?t?? ? s?s?et?se?? ?a e?s?µat??eta? se
  p??a?a ????? ??t?t?ta?.

26

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???

• ?? ?p???s??µe ?p???e?t??? s?µµet???.
• S?s??t?s? 11. ?pa?te?ta? 1 p??a?a? (µe ??a ta
  ?a?a?t???st???).
• S?s??t?s? 1?. ?pa?t???ta? 2 p??a?e? (??a? ??a
  ???e s????? ??t?t?t??, ?a? ???? ??e?d? st??
  p??a?a t?? p?e???? ?, t? ????? ??e?d? t?? p??a?a
  t?? p?e???? 1).
• S?s??t?s? ??. ?pa?t???ta? 3 p??a?e? (??a? ??a
  ???e s????? ??t?t?t??, ?a? ??a? ??a t? s?????
  s?s?et?se??).

27

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???

• ?? ?p???s??µe p??a??et??? s?µµet???.
• ?e ß?s? ta p??????µe?a, ?a ????µe ?e??? t?µ??.

28

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???

• ?? ?p???s??µe p??a??et??? s?µµet???.
• S?s??t?s? 11.
• apa?t???ta? 2 p??a?e? a? µ??? t? ??a s?????
  ??t?-t?t?? s?µµet??e? p??a??et???. St?? p??a?a
  t?? ?p?-??e?t???? p?e???? µet??e? t? ??e?d? t??
  p??a??et???? p?e???? ?a? ta ?a?a?t???st??? t??
  s?s??t?s??.
• apa?t???ta? 3 p??a?e? a? ?a? ta d?? s????a
  ??t?t?t?? s?µµet????? p??a??et??? (??a? p??a?a?
  ??a t? s?s??t?s?).

29

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???

• ?? ?p???s??µe p??a??et??? s?µµet???.
• S?s??t?s? 1?.
• apa?t???ta? 2 p??a?e? a? µ??? t? s????? ??t?t?t??
  t?? 1 p?e???? s?µµet??e? p??a??et???. St?? p??a?a
  t?? ?p???e?t???? p?e???? µet??e? t? ??e?d? t??
  p??a??et???? p?e???? ?a? ta ?a?a?t???st??? t??
  s?s??t?s??.
• apa?t???ta? 3 p??a?e? a? µ??? t? s????? ??t?t?t??
  t?? ? p?e???? s?µµet??e? p??a??et??? ? a? ?a? ta
  d?? s????a ??t?t?t?? s?µµet????? p??a??et???
  (??a? p??a?a? ??a t? s?s??t?s?).

30

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???

• ?? ?p???s??µe p??a??et??? s?µµet???.
• S?s??t?s? ??.
• Se ???e pe??pt?s? apa?t???ta? 3 p??a?e?.

31

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???
32

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???
33

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???

• S?s?et?se?? a??te??? ßa?µ?? d d1 p??a?e?.
• ?a?a?t???st??? p???ap??? t?µ?? ?e????st??
  p??a?a? µe t? ??e?d? t?? a?t?st????? s??s??.
• ?d??aµe? ??t?t?te? ?e????st?? p??a?a? µe
  d?a???t??? s?? ??e?d? t?? a?t?st????? s??s??
• ??e?d??e?s?/?e???e?s? ??a? p??a?a? ??a ???e
  ???s?/ ?p????s? (a? de? ?p???e? ??????, t?te de?
  ??e???eta? p??a?a? ??a ???s?).
• S?ss?µ?t?s? ??a? ?e????st?? p??a?a? µe s???et?
  ??e?d?.

34

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???
35

?ef??a?? 6 S?es?a?? ???t???
?etat??p? ?S µ??t???? se S?es?a?? µ??t???
36

?ef??a?? 6 S?es?a?? ???t???
??e??

• ??a ??? e??a? µ?a e??????? (virtual) ? pa?a??µe??
  (derived) s??s?, p?? p????pte? ap? µ?a ?
  pe??ss?te?e? ßas???? s??se?? (base relations).
• ?? ßas???? s??se?? ????? f?s??? ?p?stas? (st?
  d?s??), e?? µ?a ??? e??a? ??a? ap??? ???sµ??.

37

?ef??a?? 6 S?es?a?? ???t???
??e??

• ?? ??e?? e??a? ???s?µe? d??t?
• pa?????? asf??e?a µe ??a? ap?? a??? ?s????
  µ??a??sµ? ap?-?????? ded?µ???? ap? s???e???µ?????
  ???ste? ? efa?µ????,
• t? ?d?? s????? ded?µ???? µp??e? ?a d??eta? st???
  ???ste? µe d?af??et??? t??p?, a?????a µe t??
  ???sµ? t?? ???? (e?e????a),
• ap??p??e?ta? ? d?at?p?s? e??t?µ?t??, ?a??? e??a?
  d??at?? p???p???e? s??d?se?? µeta?? t?? s??se??
  ?a ?µad?p??????? µ?sa st?? ???sµ? t?? ????.

38

?ef??a?? 6 S?es?a?? ???t???
??e?? (Views)
39

?ef??a?? 6 S?es?a?? ???t???
???p???µ??e? ??e?? (Materialized Views)

• ?p???e? µ?a ?at?????a ??e?? µe f?s??? ?p?stas?,
  ?? ?p??e? ?a????ta? ???p???µ??e? (materialized).
• ?? ??e?? t?t???? t?p?? ???s?µ?p?????ta? ??????
  ??a ?????? ta??t?ta? st?? epe?e??as?a t??
  ded?µ????.

40

?ef??a?? 6 S?es?a?? ???t???
S?????

• ?? s?es?a?? µ??t??? a?apt?????e ap? t?? Codd t?
  1970.
• G?????e? µe???? ap???s? st? ß??µ??a??a (RDBMS).
• ???s?µ?p??e? s??se?? (p??a?e?) ??a t??
  a?apa??stas? t?? ded?µ????. ???e p??a?a?
  ap?te?e?ta? ap? ??a s????? p?e??d?? (??aµµ??) ?a?
  ?a?a?t???st???? (st????).
• ??a ? pe??ss?te?a ?a?a?t???st??? ??????? t?
  p??te??? ??e?d? t?? p??a?a. ??? p?e??de? de?
  µp????? ?a s?µf????? st?? t?µ? t?? ??e?d???.
• ???e st??? ?aµß??e? t?µ?? ap? ??p??? ped??
  ???sµ?? µe at?µ???? t?µ?? se ???e ?e??.
• ?e pe?????sµ??? a?e?a??t?ta? d?at??e?ta? ? ?a??
  ?at?stas? t?? ded?µ???? µet? ap? e?sa?????,
  d?a??af?? ?a? e??µe??se??.
• ?? ??e?? ap?te???? µ??a??sµ? ap??????? ded?µ????
  ?a? ap??p???s?? t?? e??t?µ?t??.