REFs vs. Foreing Key.

Hi,
I am new in ORACLE Objects technology.
In my database i have two tables and i want to connect them. I usually use the primary-foreing key concept.
I want to know if REF has best perfomance than foreing key? or the only advantage is the deref functionality of SQL?
Does somebody know something about it?
Thanks
Fernando Fiszman

I'll disagree with that.
A REF is very much like a foreign key. The REF is more flexible because a REF of a particular type is not limited to pointing to exactly one table as a FK is. But a FK is more stabile because it's validity is guaranteed, whereas a REF can dangle. The impact of this is that the REF will support a wider variety of modelling scenarios, but may suffer from integrity problems unless you SCOPE the REF, in which case it is very much like an FK as it must point to exactly one table.
The REF is a pointer who's VALUE is hidden from the user, which violates Codd's information principle. This will be an issue during replication and data migration. De-referencing REFs is very much like the 'pointer chasing' that was so prevalent in pre-relational databases. The relational equivalent of 'de-referencing a REF' is joining a foreign key to it's associated primary key and returning the row of the parent table.
Anyway, while I guess it is true that an FK and a REF are different beasts, they are very similar, and it is not incorrect to view them as related.
Chris

Similar Messages

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Thanks in advance,
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Hello.
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Create WDA Input field for currency amount ref to curr key

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Hello Agnis Virtinova Avency,
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Foring Key Columns

After usage of Database Design Transformer I've accept Server Model Diagramm without FK Columns. All FK and relation in ER is OK.
When I've generate DDL scripts for tables I have not seen this columns eather.
Whats wrong (excluding my english :))?

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Gints Plivna ([email protected]):
A little bit didn't understand
1. If You haven't FK columns and Foreign Keys on tables You cannot generate tables with them :)
2. If You have these columns and keys then check options -> general options -> database -> "generate integrity constraints" and "foreign key generation requires join table" assuming you are using Design Editor 6.xxx
<HR></BLOCKQUOTE>
Thank You for help, but problem occured when'
I use Transformer. I try to solve it by Your advise, but it only possible if Database Design Transformer uses Design Editor Preferences.
I did not generate tables I've jult look through DDL scripts and have not found any FK columns.
The main problem is 'I have not ANY FK columns in my Server Model Diagramm'
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null

Foreing key 와 Primary key 비교해서 결과 추출

안녕하세요
참조 하고 있는 테이블을 비교하고 싶어서요.
A테이블의 . pk 컬럼과 B테이블의 fk. 컬럼이 서로 부모,자식으로
연결되었다고 가정하면 두 테이블을 비교해서 다른 컬럼(즉 Foreign key이 깨진것)
을 확인하고 싶어요.....간단하면서 막상 할려니 머리를 헤매네요...
( FILES.filesid 와 ITEM.itemsno)를 조인해서 한쪽에 없는 값을
리스트로 출력할려구요..
글 수정:
user541094

원래 포럼에 너무 제가 글을 많이 써서 자제를 하려고 했는데..
temp관련해서 스크립트를 실수해서 글 수정하다가..
답변드립니다.
부모자식관계는 아래와 같이 확인하시면 됩니다.
dept테이블의 deptno 컬럼을 pk로 하고, emp테이블에서 dept의 deptno 컬럼을 reference해서 사용합니다.
즉 부모가 dept 테이블 이고 자식이 emp 테이블
### dept(deptno가 pk) -< emp(deptno가 fk)
SQL> alter table dept add constraints pk_deptno primary key (deptno);
Table altered.
Elapsed: 00:00:00.40
SQL> alter table emp add constraints fk_deptno
2 foreign key (deptno)
3 references dept
4 /
## fk_const_to.sql
DOC
file: fk_const.sql
자신의 테이블에서 다른 테이블의 pk를 받아서 FK가 되는 경우,
자식을 넣으면 부모가 출력
dept(deptno가 pk) -< emp(deptno가 fk) 일 경우 emp를 넣으면
dept 테이블 출력
set line 132
col owner format a10 heading 'Pk_owner'
column table_name format a15 heading 'Pk_table'
column const_name format a15 heading 'Pk_const'
column referencing_table format a25 heading 'Ref_Table'
column referencing_table format a15 heading 'Fk_Table'
column foreign_const format a15 heading 'Fk_Const'
column fk_status format a8 heading 'Fk_Status'
column key_column format a8 heading 'Key_col'
column validated format a8 trunc
column DEFERRED format a8 trunc
column DEFERRABLE format a8 trunc
select a.owner,
a.table_name,
a.constraint_name const_name,
b.table_name referencing_table,
b.constraint_name foreign_const,
c.column_name key_column,
b.status fk_status,
b.validated ,
b.deferred,
b.deferrable
from dba_constraints a, dba_constraints b, all_cons_columns c
where
a.owner=b.owner and a.owner=c.owner
and a.constraint_name= c.constraint_name
and a.constraint_name = b.r_constraint_name
and b.table_name = upper('&table_name')
and b.constraint_type = 'R'
and a.owner not in ('SYS','SYSTEM','OUTLN','PERFSTAT')
order by 1,2,3,4
clear columns
- 결과
Enter value for table_name: emp
old 16: and b.table_name = upper('&table_name')
new 16: and b.table_name = upper('emp')
PK owner PK_table PK_const Fk_Table Fk_Const Key_col Fk_Statu VALIDATE DEFERRED DEFERRAB
SCOTT DEPT PK_DEPTNO EMP FK_DEPTNO DEPTNO ENABLED VALIDATE IMMEDIAT NOT DEFE
## fk_const_from.sql
DOC
file: fk_const_from.sql
다른 테이블의 fk가 자신의 테이블의 pk를 reference하는 경우,
부모를 넣으면 자식이 출력,
dept(deptno가 pk) -< emp(deptno가 fk) 일 경우 dept를 넣으면
emp 테이블 출력
set line 132
col owner format a10 heading 'Pk_owner'
column table_name format a15 heading 'Pk_table'
column const_name format a15 heading 'Pk_const'
column referencing_table format a25 heading 'Ref_Table'
column referencing_table format a15 heading 'Fk_Table'
column foreign_const format a15 heading 'Fk_Const'
column fk_status format a8 heading 'Fk_Status'
column key_column format a8 heading 'Key_col'
column validated format a8 trunc
column DEFERRED format a8 trunc
column DEFERRABLE format a8 trunc
select a.owner,
a.table_name,
a.constraint_name const_name,
b.table_name referencing_table,
b.constraint_name foreign_const,
c.column_name key_column,
b.status fk_status,
b.validated ,
b.deferred,
b.deferrable
from dba_constraints a, dba_constraints b, all_cons_columns c
where
a.owner=b.owner and a.owner=c.owner
and a.constraint_name= c.constraint_name
and a.constraint_name = b.r_constraint_name
and a.table_name = upper('&table_name')
and b.constraint_type = 'R'
and a.owner not in ('SYS','SYSTEM','OUTLN','PERFSTAT')
order by 1,2,3,4
clear columns
Enter value for table_name: dept
old 16: and a.table_name = upper('&table_name')
new 16: and a.table_name = upper('dept')
PK owner PK_table PK_const Fk_Table Fk_Const Key_col Fk_Statu VALIDATE DEFERRED DEFERRAB
SCOTT DEPT PK_DEPTNO EMP FK_DEPTNO DEPTNO ENABLED VALIDATE IMMEDIAT NOT DEFE

Foreing keys works only when created as CAPITAL?

Hello,
When working with HTML DB tutorial, I have noticed that foreign keys works only when I do create them as CAPITAL. I did create some foreign keys manually, and when I was trying "query by example" it did not work correctly unles I did re-create the foreign keys using all captials in their name. Why is it that?
Thank you,
DanielD

I let it dry out more and it started working. It still has a quirk or two but I can live with it.

Can foreign key refer to unique key?

Hi....

If you join that table x with table y using a
WHERE x.pk_column = y.fk_columnpredicate. Then the rows with "matching" NULL's will not show up in the query result.
But this has nothing to do with an FK referencing a UK.
It has everything to do with how NULL's are treated in the SQL standard.
A predicate like:
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Hi,
I Am new to adf business components. I Am using jdeveloper 11g and mysql5.1 i tried just create one master detail entry, but i can't create association entity class using adf business components. How can i create this? Please help me.
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Wrong order foreign key constraints

Hi,
i have problems with non-deferred foreing key constraints:
I have a table "PERSON" and a table "ADRESSE" which has a foreign key
to "PERSON". Both tables have primary keys with two columns.
In the mappings I use application identity. The mappings are generated by
xdoclet.
We cannot use deferred constraint because we have to support following
databases: Oracle, Firebird, MS SQL, DB2.
I tested the mappings with Oracle and Firebird and got this exception
(with SQL Trace):
5602 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (1 errors)>
[15 ms] executing prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART,
EMAIL, FAXNR, ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ,
POSTADRESSE, POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?,
?, ?, ?, ?, ?, ?) [params=(int) 1, (String) [email protected], (String)
04941 183742, (int) 12761, (int) 1, (int) 1, (String) 0171 2846751,
(String) Oldenburg, (int) 12760, (String) 26129, (int) 1, (null) null,
(String) Ammerl__nder Heerstra__e 19, (String) 04941 183740] [reused=0]
5602 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (2 errors)>
[0 ms] executing prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART,
EMAIL, FAXNR, ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ,
POSTADRESSE, POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?,
?, ?, ?, ?, ?, ?) [params=(int) 3, (null) null, (null) null, (int) 12764,
(int) 1, (int) 0, (null) null, (String) Sylt, (int) 12759, (String) 25980,
(int) 0, (null) null, (String) Stephanstra__e 47, (String) 04651 19283]
[reused=1]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (2 errors)>
[0 ms] executing prepstmnt 13390902 INSERT INTO VAMP.PERSON (ANREDEID, ID,
KUNDENNR, LOESCHBEMERKUNG, MANDANTID, NAME1, NAME2, PERSONENDATUM,
PERSONENORT, TYP) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?) [params=(null)
null, (int) 12759, (String) 9999452800, (null) null, (int) 1, (String)
Horstmann, (String) Manfred, (Timestamp) 1959-03-10 00:00:00.381, (String)
Flensburg, (int) 1] [reused=0]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (2 errors)>
[0 ms] executing prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART,
EMAIL, FAXNR, ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ,
POSTADRESSE, POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?,
?, ?, ?, ?, ?, ?) [params=(int) 1, (String) [email protected], (String)
04941 183742, (int) 12763, (int) 1, (int) 1, (String) 0171 2846751,
(String) Oldenburg, (int) 12759, (String) 26129, (int) 1, (null) null,
(String) Ammerl__nder Heerstra__e 19, (String) 04941 183740] [reused=2]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (3 errors)>
[0 ms] executing prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART,
EMAIL, FAXNR, ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ,
POSTADRESSE, POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?,
?, ?, ?, ?, ?, ?) [params=(int) 3, (null) null, (null) null, (int) 12762,
(int) 1, (int) 0, (null) null, (String) Sylt, (int) 12760, (String) 25980,
(int) 0, (null) null, (String) Stephanstra__e 47, (String) 04651 19283]
[reused=3]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (3 errors)>
[0 ms] executing prepstmnt 13390902 INSERT INTO VAMP.PERSON (ANREDEID, ID,
KUNDENNR, LOESCHBEMERKUNG, MANDANTID, NAME1, NAME2, PERSONENDATUM,
PERSONENORT, TYP) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?) [params=(null)
null, (int) 12760, (String) 9999452801, (null) null, (int) 1, (String)
Horstmann, (String) Christine, (Timestamp) 1972-03-10 00:00:00.381,
(String) Erfurt, (int) 1] [reused=1]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (3 errors)>
[0 ms] executing prepstmnt 11320634 INSERT INTO VAMP.NATPERSON
(ANZAHLKINDER, ARBEITGEBERID, BEITRAGSSATZ, BERUFID, BRANCHEID,
FAMILIENSTAND, FAMSTANDSEIT, FINANZAMTID, GEBIETSFREMDERAWG, GUETERSTAND,
IDBEHOERDE, IDNR, KIRCHENSTEUER, KVID, MANDANTID, PERSONID, PRIVATKV,
STAAT, STEUERBERATERID, STEUERKLASSE, STEUERNR, STEUERTARIF, TITEL) VALUES
[params=(int) 0, (null) null, (double) 0.0, (null) null, (int) 12410,
(int) 2, (Timestamp) 1991-12-12 00:00:00.381, (null) null, (int) 0, (int)
3, (null) null, (null) null, (int) 0, (int) 12576, (int) 1, (int) 12760,
(int) 0, (null) null, (null) null, (int) 0, (null) null, (int) 1, (null)
null] [reused=0]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (3 errors)>
[0 ms] executing prepstmnt 11320634 INSERT INTO VAMP.NATPERSON
(ANZAHLKINDER, ARBEITGEBERID, BEITRAGSSATZ, BERUFID, BRANCHEID,
FAMILIENSTAND, FAMSTANDSEIT, FINANZAMTID, GEBIETSFREMDERAWG, GUETERSTAND,
IDBEHOERDE, IDNR, KIRCHENSTEUER, KVID, MANDANTID, PERSONID, PRIVATKV,
STAAT, STEUERBERATERID, STEUERKLASSE, STEUERNR, STEUERTARIF, TITEL) VALUES
[params=(int) 0, (null) null, (double) 0.0, (int) 12362, (int) 12378,
(int) 2, (Timestamp) 1991-12-12 00:00:00.381, (null) null, (int) 0, (int)
3, (null) null, (null) null, (int) 0, (int) 12576, (int) 1, (int) 12759,
(int) 0, (null) null, (null) null, (int) 0, (null) null, (int) 1, (null)
null] [reused=1]
5634 TRACE [main] kodo.jdbc.JDBC - <t 26577913, conn 33108879 (3
errors)> [16 ms] rollback
5634 TRACE [main] kodo.jdbc.JDBC - <t 26577913, conn 33108879 (3
errors)> return
5634 TRACE [main] kodo.jdbc.JDBC - <t 26577913, conn 33108879 (3
errors)> [0 ms] close
com.solarmetric.jdbc.ReportingSQLException: ORA-02291: integrity
constraint (VAMP.ADRESSE_PS) violated - parent key not found
{prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART, EMAIL, FAXNR,
ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ, POSTADRESSE,
POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?,
?, ?) [params=(int) 1, (String) [email protected], (String) 04941
183742, (int) 12761, (int) 1, (int) 1, (String) 0171 2846751, (String)
Oldenburg, (int) 12760, (String) 26129, (int) 1, (null) null, (String)
Ammerl__nder Heerstra__e 19, (String) 04941 183740] [reused=0]} [code=2291,
state=23000]
     at
com.solarmetric.jdbc.LoggingConnectionDecorator.wrap(LoggingConnectionDecorator.java:124)
     at
com.solarmetric.jdbc.LoggingConnectionDecorator.access$600(LoggingConnectionDecorator.java:19)
     at
com.solarmetric.jdbc.LoggingConnectionDecorator$LoggingConnection$LoggingPreparedStatement.executeUpdate(LoggingConnectionDecorator.java:728)
     at
com.solarmetric.jdbc.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:362)
How can I force it to insert in the table "NATPERSON" first and then in
the table "ADRESSE"?
I use following JDBC-drivers:
Firebird: 1.5.5
Oracle: 9.2.0.1.0
My property file:

<prop key="kodo.LicenseKey">LICENSE KEY REMOVED</prop>
<prop key="kodo.ConnectionFactoryProperties">MaxCachedStatements=150,
MaxActive=50, MaxIdle=50</prop>
<prop key="kodo.FetchBatchSize">200</prop>
<prop key="kodo.DataCache">true(CacheSize=5000)</prop>
<prop key="kodo.RemoteCommitProvider">sjvm</prop>
<prop key="kodo.jdbc.MappingFactory">metadata</prop>
<prop key="kodo.jdbc.ForeignKeyConstraints">true</prop>
<prop key="kodo.jdbc.SchemaFactory">native</prop>
<prop
key="javax.jdo.PersistenceManagerFactoryClass">kodo.jdbc.runtime.JDBCPersistenceManagerFactory</prop>
<prop key="javax.jdo.option.Optimistic">true</prop>

<prop key="kodo.jdbc.DBDictionary">oracle</prop>
<prop
key="javax.jdo.option.ConnectionDriverName">oracle.jdbc.driver.OracleDriver</prop>
<prop key="javax.jdo.option.ConnectionURL">..</prop>
<prop key="javax.jdo.option.ConnectionUserName">..</prop>
<prop key="javax.jdo.option.ConnectionPassword">..</prop>
<prop key="kodo.jdbc.SequenceFactory">native</prop>
<prop key="kodo.jdbc.Schemas">..</prop>

My database schema looks like this:
TABLE PERSON
FIELD MANDANTID (SMALLINT REQUIRED COMMENT (""))
FIELD ID (AUTOINC COMMENT (""))
FIELD TYP (SMALLINT REQUIRED COMMENT (""))
FIELD KUNDENNR (CHAR(15) COMMENT ("Kundennummer"))
PRIMARY KEY
FIELD MANDANTID
FIELD ID
FOREIGN KEY MD
TABLE MANDANT
FIELD MANDANTID
INDEX KDNR
FIELD MANDANTID
FIELD KUNDENNR
UNIQUE
TABLE ADRESSE
FIELD MANDANTID (SMALLINT REQUIRED COMMENT (""))
FIELD ID (AUTOINC COMMENT (""))
FIELD PERSONID (LONGINT REQUIRED COMMENT (""))
PRIMARY KEY
FIELD MANDANTID
FIELD ID
FOREIGN KEY PS
TABLE PERSON
FIELD MANDANTID
FIELD PERSONID
My metadata looks like this:
<class name="PersonDO"
identity-type="application"
objectid-class="com.elaxy.vamp.dom.person.PersonDOId"
persistence-capable-superclass="com.elaxy.vamp.dom.AbstractDO">
<extension vendor-name="kodo"
key="jdbc-class-ind"
value="metadata-value">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-ind/column"
value="TYP">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-ind-value"
value="-1">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-map"
value="base">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-map/table"
value="PERSON">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id/jdbc-field-map"
value="value">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id/jdbc-field-map/column"
value="ID">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId/jdbc-field-map"
value="value">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId/jdbc-field-map/column"
value="MANDANTID">
</extension>
<field name="kundenNr"
persistence-modifier="persistent">
</field>
<field name="adressen"
persistence-modifier="persistent">
<collection
element-type="com.elaxy.vamp.dom.person.AdresseDO">
</collection>
<extension vendor-name="kodo"
key="jdbc-field-map"
value="one-many">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-map/ref-column.MANDANTID"
value="MANDANTID">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-map/ref-column.ID"
value="PERSONID">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-map/table"
value="ADRESSE">
</extension>
</field>
.. fields ..
</class>
<class name="AdresseDO"
identity-type="application"
objectid-class="com.elaxy.vamp.dom.person.AdresseDOId"
persistence-capable-superclass="com.elaxy.vamp.dom.AbstractDO">
<extension vendor-name="kodo"
key="jdbc-class-map"
value="base">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-map/table"
value="ADRESSE">
</extension>
<extension vendor-name="kodo"
key="jdbc-sequence-name"
value="ADRESSE_SEQ">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id/jdbc-field-map"
value="value">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id/jdbc-field-map/column"
value="ID">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId/jdbc-field-map"
value="value">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId/jdbc-field-map/column"
value="MANDANTID">
</extension>
.. fields ..
</class>
Many thanks,
Jan

Marc
This is a part of the output from the "schemagen" tool:
<schemas>
<schema name="VAMP">
<table name="ADRESSE">
<pk name="ADRESSE_PRIMARY">
<on column="ID"/>
<on column="MANDANTID"/>
</pk>
<column name="ADRESSART" type="decimal" type-name="NUMBER"
size="5"/>
<column name="EMAIL" type="varchar" type-name="VARCHAR2"
size="30"/>
<column name="FAXNR" type="varchar" type-name="VARCHAR2"
size="25"/>
<column name="ID" type="decimal" type-name="NUMBER"
not-null="true" size="10"/>
<column name="LAND" type="decimal" type-name="NUMBER"
size="10"/>
<column name="MANDANTID" type="decimal" type-name="NUMBER"
not-null="true" size="5"/>
<column name="MELDEADRESSE" type="decimal" type-name="NUMBER"
size="1"/>
<column name="MOBILNR" type="varchar" type-name="VARCHAR2"
size="25"/>
<column name="ORT" type="varchar" type-name="VARCHAR2"
size="30"/>
<column name="PERSONID" type="decimal" type-name="NUMBER"
not-null="true" size="10"/>
<column name="PLZ" type="varchar" type-name="VARCHAR2"
size="5"/>
<column name="POSTADRESSE" type="decimal" type-name="NUMBER"
size="1"/>
<column name="POSTFACH" type="varchar" type-name="VARCHAR2"
size="10"/>
<column name="STRASSE" type="varchar" type-name="VARCHAR2"
size="30"/>
<column name="TELEFONNR" type="varchar" type-name="VARCHAR2"
size="25"/>
<fk name="ADRESSE_PS" delete-action="cascade"
to-table="VAMP.PERSON">
<join column="MANDANTID" to-column="MANDANTID"/>
<join column="PERSONID" to-column="ID"/>
</fk>
<index name="ADRESSE_ORT">
<on column="MANDANTID"/>
<on column="ORT"/>
</index>
<index name="ADRESSE_PLZ">
<on column="MANDANTID"/>
<on column="PLZ"/>
</index>
<index name="ADRESSE_PS">
<on column="MANDANTID"/>
<on column="PERSONID"/>
</index>
<index name="ADRESSE_STR">
<on column="MANDANTID"/>
<on column="STRASSE"/>
</index>
</table>
The foreign key "ADRESSE_PS" was identified correctly.
I've taken a look at the class OracleDictionary and it seems that the
object "ForeignKey" considers only one column from the foreign keys -
but I use foreign keys that include two columns ("MANDANTID", "PERSONID").
Is that right or are foreign keys with two columns allowed by the
OracleDictionary?
Marc Prud'hommeaux wrote:
Jan-
That is odd ... Kodo should be identifying the foreign keys and ordering
the statements accordingly. The mappings appear correct to me at first
glance. If you run the "schemagen" tool, does Kodo correctly identify
the foreign key constraints in the database? Can you post the output
from the command so we can take a look?
Jan-Esdert Franken wrote:
Hi,
i have problems with non-deferred foreing key constraints:
I have a table "PERSON" and a table "ADRESSE" which has a foreign key
to "PERSON". Both tables have primary keys with two columns.
In the mappings I use application identity. The mappings are generated by
xdoclet.
We cannot use deferred constraint because we have to support following
databases: Oracle, Firebird, MS SQL, DB2.
I tested the mappings with Oracle and Firebird and got this exception
(with SQL Trace):
5602 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (1 errors)>
[15 ms] executing prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART,
EMAIL, FAXNR, ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ,
POSTADRESSE, POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?,
?, ?, ?, ?, ?, ?) [params=(int) 1, (String) [email protected], (String)
04941 183742, (int) 12761, (int) 1, (int) 1, (String) 0171 2846751,
(String) Oldenburg, (int) 12760, (String) 26129, (int) 1, (null) null,
(String) Ammerl__nder Heerstra__e 19, (String) 04941 183740] [reused=0]
5602 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (2 errors)>
[0 ms] executing prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART,
EMAIL, FAXNR, ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ,
POSTADRESSE, POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?,
?, ?, ?, ?, ?, ?) [params=(int) 3, (null) null, (null) null, (int) 12764,
(int) 1, (int) 0, (null) null, (String) Sylt, (int) 12759, (String) 25980,
(int) 0, (null) null, (String) Stephanstra__e 47, (String) 04651 19283]
[reused=1]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (2 errors)>
[0 ms] executing prepstmnt 13390902 INSERT INTO VAMP.PERSON (ANREDEID, ID,
KUNDENNR, LOESCHBEMERKUNG, MANDANTID, NAME1, NAME2, PERSONENDATUM,
PERSONENORT, TYP) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?) [params=(null)
null, (int) 12759, (String) 9999452800, (null) null, (int) 1, (String)
Horstmann, (String) Manfred, (Timestamp) 1959-03-10 00:00:00.381, (String)
Flensburg, (int) 1] [reused=0]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (2 errors)>
[0 ms] executing prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART,
EMAIL, FAXNR, ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ,
POSTADRESSE, POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?,
?, ?, ?, ?, ?, ?) [params=(int) 1, (String) [email protected], (String)
04941 183742, (int) 12763, (int) 1, (int) 1, (String) 0171 2846751,
(String) Oldenburg, (int) 12759, (String) 26129, (int) 1, (null) null,
(String) Ammerl__nder Heerstra__e 19, (String) 04941 183740] [reused=2]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (3 errors)>
[0 ms] executing prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART,
EMAIL, FAXNR, ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ,
POSTADRESSE, POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?,
?, ?, ?, ?, ?, ?) [params=(int) 3, (null) null, (null) null, (int) 12762,
(int) 1, (int) 0, (null) null, (String) Sylt, (int) 12760, (String) 25980,
(int) 0, (null) null, (String) Stephanstra__e 47, (String) 04651 19283]
[reused=3]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (3 errors)>
[0 ms] executing prepstmnt 13390902 INSERT INTO VAMP.PERSON (ANREDEID, ID,
KUNDENNR, LOESCHBEMERKUNG, MANDANTID, NAME1, NAME2, PERSONENDATUM,
PERSONENORT, TYP) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?) [params=(null)
null, (int) 12760, (String) 9999452801, (null) null, (int) 1, (String)
Horstmann, (String) Christine, (Timestamp) 1972-03-10 00:00:00.381,
(String) Erfurt, (int) 1] [reused=1]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (3 errors)>
[0 ms] executing prepstmnt 11320634 INSERT INTO VAMP.NATPERSON
(ANZAHLKINDER, ARBEITGEBERID, BEITRAGSSATZ, BERUFID, BRANCHEID,
FAMILIENSTAND, FAMSTANDSEIT, FINANZAMTID, GEBIETSFREMDERAWG, GUETERSTAND,
IDBEHOERDE, IDNR, KIRCHENSTEUER, KVID, MANDANTID, PERSONID, PRIVATKV,
STAAT, STEUERBERATERID, STEUERKLASSE, STEUERNR, STEUERTARIF, TITEL) VALUES
[params=(int) 0, (null) null, (double) 0.0, (null) null, (int) 12410,
(int) 2, (Timestamp) 1991-12-12 00:00:00.381, (null) null, (int) 0, (int)
3, (null) null, (null) null, (int) 0, (int) 12576, (int) 1, (int) 12760,
(int) 0, (null) null, (null) null, (int) 0, (null) null, (int) 1, (null)
null] [reused=0]
5618 TRACE [main] kodo.jdbc.SQL - <t 26577913, conn 33108879 (3 errors)>
[0 ms] executing prepstmnt 11320634 INSERT INTO VAMP.NATPERSON
(ANZAHLKINDER, ARBEITGEBERID, BEITRAGSSATZ, BERUFID, BRANCHEID,
FAMILIENSTAND, FAMSTANDSEIT, FINANZAMTID, GEBIETSFREMDERAWG, GUETERSTAND,
IDBEHOERDE, IDNR, KIRCHENSTEUER, KVID, MANDANTID, PERSONID, PRIVATKV,
STAAT, STEUERBERATERID, STEUERKLASSE, STEUERNR, STEUERTARIF, TITEL) VALUES
[params=(int) 0, (null) null, (double) 0.0, (int) 12362, (int) 12378,
(int) 2, (Timestamp) 1991-12-12 00:00:00.381, (null) null, (int) 0, (int)
3, (null) null, (null) null, (int) 0, (int) 12576, (int) 1, (int) 12759,
(int) 0, (null) null, (null) null, (int) 0, (null) null, (int) 1, (null)
null] [reused=1]
5634 TRACE [main] kodo.jdbc.JDBC - <t 26577913, conn 33108879 (3
errors)> [16 ms] rollback
5634 TRACE [main] kodo.jdbc.JDBC - <t 26577913, conn 33108879 (3
errors)> return
5634 TRACE [main] kodo.jdbc.JDBC - <t 26577913, conn 33108879 (3
errors)> [0 ms] close
com.solarmetric.jdbc.ReportingSQLException: ORA-02291: integrity
constraint (VAMP.ADRESSE_PS) violated - parent key not found
{prepstmnt 22511833 INSERT INTO VAMP.ADRESSE (ADRESSART, EMAIL, FAXNR,
ID, MANDANTID, MELDEADRESSE, MOBILNR, ORT, PERSONID, PLZ, POSTADRESSE,
POSTFACH, STRASSE, TELEFONNR) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?,
?, ?) [params=(int) 1, (String) [email protected], (String) 04941
183742, (int) 12761, (int) 1, (int) 1, (String) 0171 2846751, (String)
Oldenburg, (int) 12760, (String) 26129, (int) 1, (null) null, (String)
Ammerl__nder Heerstra__e 19, (String) 04941 183740] [reused=0]} [code=2291,
state=23000]
     at
com.solarmetric.jdbc.LoggingConnectionDecorator.wrap(LoggingConnectionDecorator.java:124)
     at
com.solarmetric.jdbc.LoggingConnectionDecorator.access$600(LoggingConnectionDecorator.java:19)
     at
com.solarmetric.jdbc.LoggingConnectionDecorator$LoggingConnection$LoggingPreparedStatement.executeUpdate(LoggingConnectionDecorator.java:728)
     at
com.solarmetric.jdbc.DelegatingPreparedStatement.executeUpdate(DelegatingPreparedStatement.java:362)
How can I force it to insert in the table "NATPERSON" first and then in
the table "ADRESSE"?
I use following JDBC-drivers:
Firebird: 1.5.5
Oracle: 9.2.0.1.0
My property file:

<prop key="kodo.LicenseKey">LICENSE KEY REMOVED</prop>
<prop key="kodo.ConnectionFactoryProperties">MaxCachedStatements=150,
MaxActive=50, MaxIdle=50</prop>
<prop key="kodo.FetchBatchSize">200</prop>
<prop key="kodo.DataCache">true(CacheSize=5000)</prop>
<prop key="kodo.RemoteCommitProvider">sjvm</prop>
<prop key="kodo.jdbc.MappingFactory">metadata</prop>
<prop key="kodo.jdbc.ForeignKeyConstraints">true</prop>
<prop key="kodo.jdbc.SchemaFactory">native</prop>
<prop
key="javax.jdo.PersistenceManagerFactoryClass">kodo.jdbc.runtime.JDBCPersistenceManagerFactory</prop>
<prop key="javax.jdo.option.Optimistic">true</prop>

<prop key="kodo.jdbc.DBDictionary">oracle</prop>
<prop
key="javax.jdo.option.ConnectionDriverName">oracle.jdbc.driver.OracleDriver</prop>
<prop key="javax.jdo.option.ConnectionURL">..</prop>
<prop key="javax.jdo.option.ConnectionUserName">..</prop>
<prop key="javax.jdo.option.ConnectionPassword">..</prop>
<prop key="kodo.jdbc.SequenceFactory">native</prop>
<prop key="kodo.jdbc.Schemas">..</prop>

My database schema looks like this:
TABLE PERSON
FIELD MANDANTID (SMALLINT REQUIRED COMMENT (""))
FIELD ID (AUTOINC COMMENT (""))
FIELD TYP (SMALLINT REQUIRED COMMENT (""))
FIELD KUNDENNR (CHAR(15) COMMENT ("Kundennummer"))
PRIMARY KEY
FIELD MANDANTID
FIELD ID
FOREIGN KEY MD
TABLE MANDANT
FIELD MANDANTID
INDEX KDNR
FIELD MANDANTID
FIELD KUNDENNR
UNIQUE
TABLE ADRESSE
FIELD MANDANTID (SMALLINT REQUIRED COMMENT (""))
FIELD ID (AUTOINC COMMENT (""))
FIELD PERSONID (LONGINT REQUIRED COMMENT (""))
PRIMARY KEY
FIELD MANDANTID
FIELD ID
FOREIGN KEY PS
TABLE PERSON
FIELD MANDANTID
FIELD PERSONID
My metadata looks like this:
<class name="PersonDO"
identity-type="application"
objectid-class="com.elaxy.vamp.dom.person.PersonDOId"
persistence-capable-superclass="com.elaxy.vamp.dom.AbstractDO">
<extension vendor-name="kodo"
key="jdbc-class-ind"
value="metadata-value">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-ind/column"
value="TYP">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-ind-value"
value="-1">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-map"
value="base">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-map/table"
value="PERSON">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id/jdbc-field-map"
value="value">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id/jdbc-field-map/column"
value="ID">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId/jdbc-field-map"
value="value">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId/jdbc-field-map/column"
value="MANDANTID">
</extension>
<field name="kundenNr"
persistence-modifier="persistent">
</field>
<field name="adressen"
persistence-modifier="persistent">
<collection
element-type="com.elaxy.vamp.dom.person.AdresseDO">
</collection>
<extension vendor-name="kodo"
key="jdbc-field-map"
value="one-many">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-map/ref-column.MANDANTID"
value="MANDANTID">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-map/ref-column.ID"
value="PERSONID">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-map/table"
value="ADRESSE">
</extension>
</field>
.. fields ..
</class>
<class name="AdresseDO"
identity-type="application"
objectid-class="com.elaxy.vamp.dom.person.AdresseDOId"
persistence-capable-superclass="com.elaxy.vamp.dom.AbstractDO">
<extension vendor-name="kodo"
key="jdbc-class-map"
value="base">
</extension>
<extension vendor-name="kodo"
key="jdbc-class-map/table"
value="ADRESSE">
</extension>
<extension vendor-name="kodo"
key="jdbc-sequence-name"
value="ADRESSE_SEQ">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id/jdbc-field-map"
value="value">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.id/jdbc-field-map/column"
value="ID">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId"
value="">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId/jdbc-field-map"
value="value">
</extension>
<extension vendor-name="kodo"
key="jdbc-field-mappings/AbstractDO.mandantId/jdbc-field-map/column"
value="MANDANTID">
</extension>
.. fields ..
</class>
Many thanks,
Jan
Marc Prud'hommeaux
SolarMetric Inc.

REF TYPE 사용 예제

제품 : SQL*PLUS
작성날짜 : 2004-04-26
REF TYPE 사용 예제
=================
. 오브젝트 reference 할 수 있는 값을 가지는 데이터 타입
. 오브젝트와 오브젝트의 관계 표현에 유용
< sample >
-- object table 생성, data insert
SQL> insert into address_tbl values ('55 Madison Ave', 'Madison',
'WI', '53715') ;
SQL> insert into address_tbl values (address('2 Avocet Drive',
'Redwood Shores', 'CA', '95054' ));
SQL> select value(p) from address_tbl p;
ADDRESS('55 Madison Ave', 'Madison', 'WI', '53715')
ADDRESS('2 Avocet Drive', 'Redwood Shores', 'CA', '95054')
-- ref의 값을 특정 table로 제한
SQL> create table address_ref_tbl
( empno number,
address_ref ref address scope is address_tbl);
-- Insert
SQL> insert into address_ref_tbl
select 10, ref(p) from address_tbl p where state = 'WI';
SQL> insert into address_ref_tbl values (20, null);
SQL> update address_ref_tbl
set address_ref = (select ref(p) from address_tbl p
where state = 'CA')
where empno = 20 ;
-- Select
SQL> select * from address_ref_tbl;
10 0000220208910A3F700F3811D3A2300010A4F93C83910A3F6F0F381 ....
20 000220208910A3F710F3811D3A2300010A4F93C83910A3F6F0F3811 ...
-- ref가 가리키는 object를 select
SQL> select empno, deref(address_ref) from address_ref_tbl;
10 ADDRESS('55 Madison Ave', 'Madison', 'WI', '53715')
20 ADDRESS('2 Avocet Drive', 'Redwood Shores', 'CA', '95055')
-- ref가 가리키는 object의 attribute를 select
SQL> select p.address_ref.zip from address_ref_tbl p;
53715
95054
-- reference하는 오브젝트의 값이 변한 경우 -> select 결과도 따라 변한다.
SQL> update address_tbl set zip = '95055' where zip= 95054;
SQL> select empno, deref(address_ref) from address_ref_tbl;
10 ADDRESS('55 Madison Ave', 'Madison', 'WI', '53715')
20 ADDRESS('2 Avocet Drive', 'Redwood Shores', 'CA', '95055')
-- update
SQL> update address_ref_tbl set address_ref =
(select ref(p) from address_tbl p where zip ='95055')

Suresh,
In the same documentation you will find that,
a REF points to a row with an OID column (system-generated or primary-key based). 'Dereferencing' a REF is accomplished by using simple dot notation. A user doesn't have to perform explicit join operation to access the referenced object.
Regards,
Geoff
Dear Experts
A REF is a logical "pointer" to a row object. It is an Oracle built-in datatype. REFs and collections of REFs model associations among objects--particularly many-to-one relationships--thus reducing the need for foreign keys.
How the ref type can reduce the need for foreing keys.
Could any body help in this regards with examples.
Suresh

REFs vs. Foreing Key.

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