Discussion: Table Schema
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Vieux 24/03/2008, 23h56   #3
Carmen Sei
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Par défaut Re: Table Schema

I think i only need 2 table is enough

CREATE TABLE programs
(
programid int NOT NULL PRIMARY KEY,
programname nvarchar(200) NOT NULL,
... )

CREATE TABLE productioncrew
(
programid int NOT NULL REFERENCES programs,
firstname nvarchar(200) NOT NULL,
lastname nvarchar(200) NOT NULL,
role nvarchar(200) NOT NULL,
PRIMARY KEY (programid, firstname, lastname, role)
)

since my DB is only 6 tables like Schedules, TVStations,
ChannelLineup, Programs, ProductionCrews and Genres

it's a very small DB and I dont' need all those ID things it's easy to
do query with above

>
> CREATE TABLE programs (programid int NOT NULL PRIMARY KEY,
> programname nvarchar(200) NOT NULL,
> ... )
>
> CREATE TABLE people (personid int NOT NULL PRIMARY KEY,
> firstname nvarchar(50) NOT NULL,
> lastname nvarchar(50) NOT NULL,
> ....)
>
> CREATE TABLE productioncrew (programid int NOT NULL REFERENCES programs,
> personid int NOT NULL REFERENCES people,
> role datatype? NOT NULL,
> PRIMARY KEY (programid, personid))
>
>As for the role I don't have knowledge enough to know how this should
>be handled. It seems reasonable that a person can participates in
>different roles in different crews, so it should not be an attribute of
>the person. (Then again, a person has a certain skill set, which may want
>to record.) A person can also have several roles in the same crew,
>which would call for even more relational tables, but depending on the
>need to query that information it may shoot over the target to have
>such tables.
>
>The important thing is that in a relational database, a basic rules is:
>no repeating groups. Repeating groups are difficult to query and
>maintain.

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