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Thread: Add new field with auto-icrement to existing table

Add new field with auto-icrement to existing table

From
Brice André
Date:
Dear all,

I have a database structure with several default empty tables defines in an admin schema. For example :

CREATE TABLE admin."ConfigurableWindowGUIEntryInternal"
(
  "DbSyncID" bigint NOT NULL,
  "DbSyncInsertedBackupVersion" bigint NOT NULL,
...
)
WITH (
  OIDS=FALSE
);

And, for each client, I have a dedicated schema with tables that derive from those admin tables, and use the two first elements as primary keys (DbSyncID and DbSyncInsertedBackupVersion). For example :

CREATE TABLE user_1."ConfigurableWindowGUIEntryInternal"
(
  CONSTRAINT "ConfigurableWindowGUIEntry_pk" PRIMARY KEY ("DbSyncID", "DbSyncInsertedBackupVersion")
)
INHERITS (admin."ConfigurableWindowGUIEntryInternal")
WITH (
  OIDS=FALSE
);

This schema is used for synchronisation of the database between the server and client applications and I do not want to change anything in this communication protocol.

But now, I would want to develop a server-based application. And this application would need a single column unique ID for referencing tables entries. My current primary key does not fit my needs as it is based on two columns. So, I would want to add a new field on all derived tables. And, as I don't want to change the synchronisation stuff, the values of this new field should be assigned automatically.

Is there a way to add this once for all by changing the parent table or do I need to add the field for each derived table ? And how can I perform this, taking into account that the tables already contain data ?

Thanks in advance for your help.

Regards,
Brice

Re: Add new field with auto-icrement to existing table

From
Andreas Kretschmer
Date:
Brice André <brice@famille-andre.be> wrote:

> But now, I would want to develop a server-based application. And this
> application would need a single column unique ID for referencing tables
> entries. My current primary key does not fit my needs as it is based on two
> columns. So, I would want to add a new field on all derived tables. And, as I
> don't want to change the synchronisation stuff, the values of this new field
> should be assigned automatically.

Create a new Sequence. I think, that should fit your requirement.

Andreas
-- 
Really, I'm not out to destroy Microsoft. That will just be a completely
unintentional side effect.                              (Linus Torvalds)
"If I was god, I would recompile penguin with --enable-fly."   (unknown)
Kaufbach, Saxony, Germany, Europe.              N 51.05082°, E 13.56889°

Re: Add new field with auto-icrement to existing table

From
Brice André
Date:
Exactly what I needed.

Thanks,
Brice

2015-01-06 18:44 GMT+01:00 Andreas Kretschmer <akretschmer@spamfence.net>:
Brice André <brice@famille-andre.be> wrote:

> But now, I would want to develop a server-based application. And this
> application would need a single column unique ID for referencing tables
> entries. My current primary key does not fit my needs as it is based on two
> columns. So, I would want to add a new field on all derived tables. And, as I
> don't want to change the synchronisation stuff, the values of this new field
> should be assigned automatically.

Create a new Sequence. I think, that should fit your requirement.

Andreas
--
Really, I'm not out to destroy Microsoft. That will just be a completely
unintentional side effect.                              (Linus Torvalds)
"If I was god, I would recompile penguin with --enable-fly."   (unknown)
Kaufbach, Saxony, Germany, Europe.              N 51.05082°, E 13.56889°


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