[v divya]

Hi all,

Can someone give me a soln on how to set primary key and how to create a foreign key in e32db..

I learn't that COUNTER will act as a primary key in e32db.. I tried it but the counter value is 0 for all my record.. Is there anyother way to set primary key..

Also say me how to set a foreign key in e32db..

[maclun123]

I am using like this:

self.db.execute(u"CREATE TABLE RelatedWLan (Id COUNTER, I_Id SMALLINT, WLan_Id SMALLINT)")

and when adding:

self.SQLdb.query(u"INSERT INTO RelatedWLan (I_Id, WLan_Id) VALUES (" + str(id) + "," + str(result[0][0]) + ")")

FK you just insert as any other other value. I did that. Above I_Id is a foregin key.

hope this helps.
mac

[v divya]

malun123 thanks for ur reply but I didn't understand ur INSERT statement.. How does I_Id became the foreign key.. So, Can it be used in any other table? Can someone pls explain on that code..

db.execute(u"CREATE TABLE Details_table(Id COUNTER, Name CHAR(20)")
db.execute(u"CREATE TABLE Settings_table(Id, Settings CHAR(20)")

Say for eg I have the above 2 tables and my 2nd table(Settings_table) should use 1st table's(Details_table) field Id value in it.. How to get this done..

Python experts I am waiting for ur replies.......

[maclun123]

My example is the manual job. I am using I_Id as a FK in my project.
I am not into SQL that much, but if you are thinking about having something like 'joins', then I am afraid that Pys60 does not support that.

mac

[v divya]

Originally Posted by maclun123

My example is the manual job. I am using I_Id as a FK in my project.
I am not into SQL that much, but if you are thinking about having something like 'joins', then I am afraid that Pys60 does not support that.

mac

Thanks for ur suggestion mac :-) I wil this and see..

Is anybody else there who can give few more examples or can help me in creating foreign and primary keys in e32db....

Pls guys I need help.......

Do reply to my post as soon as possible.....

Thanks in advance....

[zarzu]

this is how you should get a primary key:

CREATE TABLE person (id COUNTER, name VARCHAR)
CREATE UNIQUE INDEX id_index ON person(id)

there is nothing like a foreign key as e32db does not support any kind of joins, so a foreign key concept doesn't make sense (if you are going to query the db twice to form a join in your program you will need your code to make sure that you only can insert valid pseudo foreign keys). e32db is very very limited.

[v divya]

Thanks zarzu.. I am now clear on primary keys..

So if I want to access any value from one table to another table, is it not at all possible in e32db?

My database design requires this aspect strictly.. What am i to do if I want to use one table values in another table.. Should i quit e32db and choose something else..

Pls clear my doubts..

[v divya]

Hello python experts... I am waiting for ur replies for my previous post... Do help in getting soln to my problem..

Can I access values from one table to another using e32db... I need this aspect in my db.. What should I do to get this done..

Plssssssss do reply as soon as possible....

Thanks in advance...