Avoiding duplications in table.
Hi All,
I have the following tables.
tablename : versions tablename :
applicationmanager tablename : applications
versionnumber-string versionnumber -
string applicationnumber - integer
applicationnumber - integer other details
tablename : profilemanager tablename : profiles
versionnumber : string versionnumber : string
profilename : string profilename : string
applicationnumber : integer
otherdetails
Primary key :
---------------
(1) versions : versionnumber
(2) applicationmanager : versionnumber, applicationnumber
(3) applications : applicationnumber
(4) profilemanager : veriosnnumber, profilename, applicationnumber
(5) profiles : versionnumber, profilename
Relations :
-----------
(1) versionnumber of 'applicationmanager' referes to versionnumber of
'versions' table.
(2) applicationnumber of 'applicationmanager' referes to
applicationnumber of 'applications' table.
(3) versionnumber and applicationnumber of 'profilemanager' referes
to versionnumber and applicationnumber of 'applicationmanager'.
(4) versionnumber and profilename of 'profilemanager' referes ot
versionnumber and profilename of 'profiles'.
(5) versionnumber of 'profiles' referes to versionnumber of
'versions'.
In the above design I can able to see duplication of data in all the
tables. If I take out a id out of all these tables to make reference, is
that problem will solve. Is that is
a correct approach.
Can any one help me.
regards,
Deepa K
For us not to struggle to read what you are doing,
please reformat your table definitions along the lines of:
tablename1
column_name1, type
column name2, type
column name3, type
tablename1
column name1, type
column name2, type
column name3, type
or
full fledged table creation statements a la:
CREATE TABLE PhonNums(
phone_num_id serial NOT NULL PRIMARY KEY,
phon_num varchar(32) NOT NULL UNIQUE,
created timestamp DEFAULT CURRENT_TIMESTAMP NOT NULL
);
PS one of the recommended ways to name attributes in a database design are:
Schemas 'ALL_CAPS_SEPARATED_WORDS' (this is a guess)
TableNames 'BumpyCaps'
FieldNames 'lower_case_underscore_separated_words'
SQLWords 'SHOULD BE ALL CAPS'
Keys/Indexes 'Often_Are_Found_With_Leading_Caps_And_Underscores'
Functions 'One_leading_cap_with_underscores' - i really don't know
Of course, PGSQL and other databases will change some of those to all caps or
all lowercase. But for readability, naming db attributes this way in SQL
statements and functions etc, helps a lot.
Deepa K wrote:
Show quoted text
Hi All,
I have the following tables.tablename : versions tablename :
applicationmanager tablename : applicationsversionnumber-string versionnumber -
string applicationnumber - integerapplicationnumber - integer other details
tablename : profilemanager tablename : profiles
versionnumber : string versionnumber : string
profilename : string profilename : stringapplicationnumber : integer
otherdetailsPrimary key :
---------------(1) versions : versionnumber
(2) applicationmanager : versionnumber, applicationnumber
(3) applications : applicationnumber
(4) profilemanager : veriosnnumber, profilename, applicationnumber
(5) profiles : versionnumber, profilenameRelations :
-----------(1) versionnumber of 'applicationmanager' referes to versionnumber of
'versions' table.
(2) applicationnumber of 'applicationmanager' referes to
applicationnumber of 'applications' table.
(3) versionnumber and applicationnumber of 'profilemanager' referes
to versionnumber and applicationnumber of 'applicationmanager'.
(4) versionnumber and profilename of 'profilemanager' referes ot
versionnumber and profilename of 'profiles'.
(5) versionnumber of 'profiles' referes to versionnumber of
'versions'.In the above design I can able to see duplication of data in all the
tables. If I take out a id out of all these tables to make reference, is
that problem will solve. Is that is
a correct approach.Can any one help me.
regards,
Deepa K---------------------------(end of broadcast)---------------------------
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