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KarateKid
10-06-02, 13:43
Hi,

I need some Experts for CODASYL, a network database system.

Is somebody with a basic knowledge in here? :)


Best Regards.
r937
10-06-02, 16:33
i used to have a pretty decent knowledge of idms

emphasis on past tense

what's the question?

rudy
http://rudy.ca/
KarateKid
10-06-02, 16:56
yeah, cool :)

I hope you can help me.

For testing a university test in germany i have to do the folowing task:



Design the following Query with CODASYL-DML:

"Which Consultant (Name) has done Calls abaout a special Software (string "Windows2000")?"

on the following relational Database:

Consultant(Id, Name, PhoneNumber, Address)
Client (Id, Name, Phonenumber, Account)
Calls(Client-Id, Consultant-Id, Software-Id, Day, Time)
Software(Number, Description)
Requires_Software(Number-1, Number-2)

But we only can use the following CODASLYL Statements:

FIND ANY <Record name> USING <Key Name>
FIND FIRST <Record name> WITHIN <Set name>
FIND NEXT <Record name> WITHIN <Set name>
FIND LAST <Record name> WITHIN <Set name>
FIND OWNER WITHIN <Set name>
FIND CURRENT <Record name> [WITHIN <Set name>]
GET <Record name>
STORE <Record name>


Thank you.
r937
10-06-02, 17:27
i don't have FIND ANY in the book i'm looking at -- presumably that's how you find the Software record for Windows2000? i'm not sure, but you have to find that record first

then find owner within calls-software

loop
if calls.software-id same as software.software-id
find owner within consultant-calls
print consultant name
endif
find next within calls-software
endloop

or something like that

i'm guessing, because you didn't say what the sets were

rudy
KarateKid
10-06-02, 18:46
thank you for that first answer,

tomorrow I try to put a Network Modell in here to show you the settypes and so on! :)