On 02.11.20 07:15, Erik Rijkers wrote:
On 2020-11-01 16:38, Jürgen Purtz wrote:
On 30.10.20 17:45, Erik Rijkers wrote:
And I wrote down some separate items:
1.
'Two Phase Locking' and 'TPL' should be, I think,
'Two-Phase Commit'. Please someone confirm.
(no changes made)
Erik Rijkers
All suggestions so far are summarized in the attached patch with the
following exceptions:
- 'Two Phase Locking' is the intended term.
OK, so what is 'Two Phase Locking'? The term is not explained, and
not used anywhere else in the manual. You propose to introduce it
here, in the tutorial. I don't know what it means, and I am not
really a beginner.
'Two Phase Locking' should be explained somewhere, and how it relates
(or not) to Two-Phase Commit (2PC), don't you agree?
Erik Rijkers
It may be possible to explain OCC and 2PL in two or three sentences
within the glossary. But I think, we shall not try to explain such
general strategies. They are not specific to PG and even not
implemented. Instead, if the paragraph is too detailed, we can use a
more general formulation without explicitly naming locking strategies.
OLD:
A first approach to implement protections against concurrent
access to the same data may be the locking of critical
rows. Two such techniques are:
<emphasis>Optimistic Concurrency Control</emphasis> (OCC)
and <emphasis>Two Phase Locking</emphasis> (2PL).
<productname>PostgreSQL</productname> implements a third, more
sophisticated technique: <firstterm>Multiversion Concurrency
Control</firstterm> (MVCC). The crucial advantage of MVCC ...
Proposal:
A first approach to implement protections against concurrent
access to the same data may be the locking of critical
rows.
<productname>PostgreSQL</productname> implements a more
sophisticated technique which avoids any locking:
<firstterm>Multiversion Concurrency
Control</firstterm> (MVCC). The crucial advantage of MVCC ...
Any thoughts or other suggestions?
--
J. Purtz
