Rakesh Kumar wrote:
>> Every row has two system columns associated with it: xmin and xmax
>>
>> xmin is the transaction ID that created the row, while xmax is
>> the transaction ID that removed the row.
>>
>> So when an update takes place, xmax of the original row and xmin
>> of the new row are set
Jeff Janes wrote:
>> I am curious because of "while xmax is the transaction ID that
>> *removed* the row".
>
> "marked for removal" would be more accurate. If the row were actually
> physically removed, it would no longer have a xmax to set.
Yes, thanks for the clarification.
I was thinking "log
On Wed, Apr 6, 2016 at 6:33 AM, Albe Laurenz wrote:
> Rakesh Kumar wrote:
> Every row has two system columns associated with it: xmin and xmax
>
> xmin is the transaction ID that created the row, while xmax is
> the transaction ID that removed the row.
>
> So when an update takes place, xmax of t
On Wed, Apr 6, 2016 at 8:35 AM, rob stone wrote:
> On Wed, 2016-04-06 at 10:33 +, Albe Laurenz wrote:
>
>
>> Every row has two system columns associated with it: xmin and xmax
>>
>> xmin is the transaction ID that created the row, while xmax is
>> the transaction ID that removed the row.
>>
>
On Wed, 2016-04-06 at 10:33 +, Albe Laurenz wrote:
> Every row has two system columns associated with it: xmin and xmax
>
> xmin is the transaction ID that created the row, while xmax is
> the transaction ID that removed the row.
>
> So when an update takes place, xmax of the original row a
On 04/06/2016 02:39 AM, Rakesh Kumar wrote:
Hello
I understand that when an update of say 100,000 rows are made, PG
writes the updated rows as a new row. These new rows are not visible
to any sessions except the one creating it. At commit time PG flips
something internally to make these rows vis
Rakesh Kumar wrote:
> I understand that when an update of say 100,000 rows are made, PG
> writes the updated rows as a new row. These new rows are not visible
> to any sessions except the one creating it. At commit time PG flips
> something internally to make these rows visible to all.
>
> My Q: w
Hello
I understand that when an update of say 100,000 rows are made, PG
writes the updated rows as a new row. These new rows are not visible
to any sessions except the one creating it. At commit time PG flips
something internally to make these rows visible to all.
My Q: what happens to those rows
