# Table without primary key **URL:** \ **Category:** Rails\ **Created:** [February 13, 2007, 12:51pm UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425 "2007-02-13T12:51:00Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Step](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/f1d935/32.png) [@Step](https://www.ruby-forum.com/u/Step)\ **Post date:** [February 13, 2007, 12:51pm UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425/1 "2007-02-13T12:51:00Z")
Hi all. I have table without in my DB. Rails try to use non-existent sequence and try to write value into non-existent primary key. And i have DB error. How to use model with such table? I try set\_sequence\_name nil set\_primary\_key nil and set\_sequence\_name “” set\_primary\_key “” - not works. Help me please. Bye. ---
**Author:** ![Step](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/f1d935/32.png) [@Step](https://www.ruby-forum.com/u/Step)\ **Post date:** [February 13, 2007, 1:03pm UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425/2 "2007-02-13T13:03:49Z")
Hi, Why don’t you just add a primary key? If you don’t have a primary key, how do you find entries in the database? Jens ---
**Author:** ![Step](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/f1d935/32.png) [@Step](https://www.ruby-forum.com/u/Step)\ **Post date:** [February 13, 2007, 1:18pm UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425/3 "2007-02-13T13:18:01Z")
> Why don’t you just add a primary key? I can not modify DB. I did not create DB. I use it only. > If you don’t have a primary key, how do you find entries in the > database? > I use SQL 🙂 > You can create table without PK and you will be able to get data 🙂 ---
**Author:** ![Step](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/f1d935/32.png) [@Step](https://www.ruby-forum.com/u/Step)\ **Post date:** [February 13, 2007, 1:37pm UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425/4 "2007-02-13T13:37:52Z")
> Why don’t you just add a primary key? > I did not create DB. I can’t modify it, only use. > If you don’t have a primary key, how do you find entries in the database? > I use SQL 🙂 ---
**Author:** ![Step](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/f1d935/32.png) [@Step](https://www.ruby-forum.com/u/Step)\ **Post date:** [February 13, 2007, 1:38pm UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425/5 "2007-02-13T13:38:52Z")
On Feb 13, 2007, at 7:18 AM, Step wrote: > > Why don’t you just add a primary key? > > I can not modify DB. I did not create DB. I use it only. Since I don’t know the answer, I’ll ask Step’s question another way: why not ask the DBA to add a primary key? > > If you don’t have a primary key, how do you find entries in the > > database? > > I use SQL 🙂 > > You can create table without PK and you will be able to get data 🙂 Of course. I think what Step wanted to know was what criteria do you use to find unique rows? Craig ---
**Author:** ![Step](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/f1d935/32.png) [@Step](https://www.ruby-forum.com/u/Step)\ **Post date:** [February 13, 2007, 1:39pm UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425/6 "2007-02-13T13:39:52Z")
Oops. In my earlier reply, I meant to reference Jens’ questions instead of Step’s. I’m sorry for any confusion. Craig ---
**Author:** ![Step](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/f1d935/32.png) [@Step](https://www.ruby-forum.com/u/Step)\ **Post date:** [February 13, 2007, 3:29pm UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425/7 "2007-02-13T15:29:15Z")
Win with set\_primary\_keys - tool for composite primary key gem --install composite\_primary\_keys ---
**Author:** ![Step](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/f1d935/32.png) [@Step](https://www.ruby-forum.com/u/Step)\ **Post date:** [February 14, 2007, 9:46am UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425/8 "2007-02-14T09:46:56Z")
> Did you or a DBA create a compound one instead of a simple one? > Or, did you have a compound one all along? > No. > Table had not any PK. > Table has not any PK now. > I tried use set\_primary\_key :column\_name but it didn’t work. When i > tried to save row i had got error. I don’t know why. > I tried use this gem and use set\_primary\_keys :column\_name - it > works. ---
**Author:** ![Step](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/f1d935/32.png) [@Step](https://www.ruby-forum.com/u/Step)\ **Post date:** [February 13, 2007, 3:42pm UTC](https://www.ruby-forum.com/t/table-without-primary-key/85425/9 "2007-02-13T15:42:06Z")
On Feb 13, 2007, at 9:29 AM, Step wrote: > Win with > set\_primary\_keys - tool for composite primary key > > gem --install composite\_primary\_keys I agree that this is a great gem, but you wrote that your table didn’t have a primary key. Did you or a DBA create a compound one instead of a simple one? Or, did you have a compound one all along? Craig