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Topic: Transactions with save point

begin transaction; - line1
...
begin transaction; save transaction aaa; - line2
...
rollback transaction aaa; commit transaction; - line 3
...
commit transaction; - line4

It is clear that the command in line4 causes disk writing in the transaction log.
Question: whether there will be a disk writing after  in line2 and line3?
The forced postponed transactions are not present.

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Re: Transactions with save point

Prolog wrote:

it is clear that the command in line4 causes disk writing in the transaction log.

by no means, does not cause

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Re: Transactions with save point

Prolog wrote:

the Question: whether there will be a disk writing after  in line2 and line3?

if absolutely  any of these  does not cause record in a broad gull.
Record in a broad gull will be between line1 and line2, for example, at the moment of the first  or .

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Re: Transactions with save point

Prolog;
Want disk writing write checkpoint

5

Re: Transactions with save point

WarAnt wrote:

Prolog;
Want disk writing write checkpoint

...And on a disk that in a broad gull collected will be dropped, but not dropped yet.
And what there also was not (as in case of the HARDWARE), does not register all the same

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Re: Transactions with save point

I, on the contrary, would like, that to finite commit' disk writings was less.

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Re: Transactions with save point

Prolog wrote:

the Question: whether there will be a disk writing after  in line2 and line3?

Can will, and can and will not be.
Physical record in  too is buffered. This buffer is dropped on a disk at its overflow or at transaction fixing.
Total (if to consider that to line1 open transactions are not present):
line1 - In  it is written nothing.
line2 - In  registers save transaction aaa. It will be possible thus buffer ZHT it is dropped on a disk.
line3 - At rollback transaction aaa in  compensating of all operations which have happened after line2 registers. It will be possible thus buffer ZHT it is dropped on a disk.
line4 - In  registers commit. Buffer ZHT will be dropped on a disk.

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Re: Transactions with save point

invm, c!
About something such I also assumed. For me it is important to understand that operations on line2 and line3 will not lead to the forced and immediate reset on a disk.