Обсуждение: How to make the row changes inside trigger function visible to the top level sql statement?

Hello,

I am doing table partitioning, all is ok except that after executing 'insert' sql statement I can't get affected rows,
italways be 0. After searching on the documents, I found that row changes inside trigger function is not visible to the
toplevel statement. 

Partition table using a trigger function to redirect insertion to the correct partition is the recommend way, and test
affectedrows is also used frequently. pgAdmin do test the affected rows too, thus when I type a new row and click save
button,it seems failed but actually succeed. 

How can I make the row changes inside the trigger function visible to the top level statement?

Thank all in advance!

On Mon, Aug 6, 2012 at 1:14 PM, haifeng liu <haifeng.813@gmail.com> wrote:
> Hello,
>
> I am doing table partitioning, all is ok except that after executing 'insert' sql statement I can't get affected
rows,it always be 0. After searching on the documents, I found that row changes inside trigger function is not visible
tothe top level statement. 
>
> Partition table using a trigger function to redirect insertion to the correct partition is the recommend way, and
testaffected rows is also used frequently. pgAdmin do test the affected rows too, thus when I type a new row and click
savebutton, it seems failed but actually succeed. 
>
> How can I make the row changes inside the trigger function visible to the top level statement?

It is usually not necessary to check it separately because if there
were no errors than the row has been inserted successfully assuming
your redirecting function is okay. However the only way to get the
inserted row back is to do it from a subsequent statement in the
partitioning case.

In your application you can use LISTEN/NOTIFY if you need to get some
specific information from trigger BTW. May be it will help somehow.

--
Sergey Konoplev

a database architect, software developer at PostgreSQL-Consulting.com
http://www.postgresql-consulting.com

Jabber: gray.ru@gmail.com Skype: gray-hemp Phone: +79160686204

On Thu, Aug 9, 2012 at 2:53 PM, Sergey Konoplev
<sergey.konoplev@postgresql-consulting.com> wrote:
>> How can I make the row changes inside the trigger function visible to the top level statement?
>
> your redirecting function is okay. However the only way to get the
> inserted row back is to do it from a subsequent statement in the
> partitioning case.

BTW I am not completely correct here. There is a solution but it is a
tricky one https://gist.github.com/59067. I am not sure if it is a
good performing one but it will work.

> In your application you can use LISTEN/NOTIFY if you need to get some
> specific information from trigger BTW. May be it will help somehow.
>
> --
> Sergey Konoplev
>
> a database architect, software developer at PostgreSQL-Consulting.com
> http://www.postgresql-consulting.com
>
> Jabber: gray.ru@gmail.com Skype: gray-hemp Phone: +79160686204



--
Sergey Konoplev

a database architect, software developer at PostgreSQL-Consulting.com
http://www.postgresql-consulting.com

Jabber: gray.ru@gmail.com Skype: gray-hemp Phone: +79160686204

On Aug 9, 2012, at 7:11 PM, Sergey Konoplev <sergey.konoplev@postgresql-consulting.com> wrote:

> On Thu, Aug 9, 2012 at 2:53 PM, Sergey Konoplev
> <sergey.konoplev@postgresql-consulting.com> wrote:
>>> How can I make the row changes inside the trigger function visible to the top level statement?
>>
>> your redirecting function is okay. However the only way to get the
>> inserted row back is to do it from a subsequent statement in the
>> partitioning case.
>
> BTW I am not completely correct here. There is a solution but it is a
> tricky one https://gist.github.com/59067. I am not sure if it is a
> good performing one but it will work.

I don't think it's a good solution for a partitioned table. Any how, thank you for the information.

>
>> In your application you can use LISTEN/NOTIFY if you need to get some
>> specific information from trigger BTW. May be it will help somehow.
>>
>> --
>> Sergey Konoplev
>>
>> a database architect, software developer at PostgreSQL-Consulting.com
>> http://www.postgresql-consulting.com
>>
>> Jabber: gray.ru@gmail.com Skype: gray-hemp Phone: +79160686204
>
>
>
> --
> Sergey Konoplev
>
> a database architect, software developer at PostgreSQL-Consulting.com
> http://www.postgresql-consulting.com
>
> Jabber: gray.ru@gmail.com Skype: gray-hemp Phone: +79160686204
>
> --
> Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org)
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