mvcc and lock

Started by postgresqlalmost 23 years ago4 messages
#1postgresql
postgresql@db.pku.edu.cn

Hi all
I have read some code on transaction part.
When the new transaction starts, it record the snapshot of database containing the current transaction id,etc. So depending on the snapshot
, the transaction decide which tuple is visible.
But transaction could also be implemented by lock. so I am not sure how
the transaction is implemented, by MVCC or Lock, or by both?
In my option, when tuple is processed in readonly mode(select), MVCC is enough. but when tuple is changed, lock is used. I am not sure whether the explanation is correct.
Thanks for any comments.
Best regards.
josh

#2Ronald Kuczek
ronald@breitenbach.pl
In reply to: postgresql (#1)
Win32 native port

Hi all,

Can someone tell me what happened with Win32 native port ?
Discussion bevore beginning of 7.4, TODO entry this time as "urgent",
but without dash. What does it mean - comes native port with 7.4 or it
doesn't ? Thanks for any information.

Best regards
Rony

#3Bruce Momjian
pgman@candle.pha.pa.us
In reply to: Ronald Kuczek (#2)
Re: Win32 native port

I will start working on it next week.

---------------------------------------------------------------------------

Ronald Kuczek wrote:

Hi all,

Can someone tell me what happened with Win32 native port ?
Discussion bevore beginning of 7.4, TODO entry this time as "urgent",
but without dash. What does it mean - comes native port with 7.4 or it
doesn't ? Thanks for any information.

Best regards
Rony

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  pgman@candle.pha.pa.us               |  (610) 359-1001
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#4Ronald Kuczek
ronald.kuczek@breitenbach.pl
In reply to: Bruce Momjian (#3)
Re: Win32 native port

Thank you, Bruce for info.

Best regards
Rony

----- Original Message -----
From: "Bruce Momjian" <pgman@candle.pha.pa.us>
To: "Ronald Kuczek" <ronald@breitenbach.pl>
Cc: <pgsql-hackers@postgresql.org>
Sent: Wednesday, March 19, 2003 3:34 PM
Subject: Re: [HACKERS] Win32 native port

I will start working on it next week.

--------------------------------------------------------------------------

-

Ronald Kuczek wrote:

Hi all,

Can someone tell me what happened with Win32 native port ?
Discussion bevore beginning of 7.4, TODO entry this time as "urgent",
but without dash. What does it mean - comes native port with 7.4 or it
doesn't ? Thanks for any information.

Best regards
Rony

---------------------------(end of broadcast)---------------------------
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http://archives.postgresql.org

--
Bruce Momjian                        |  http://candle.pha.pa.us
pgman@candle.pha.pa.us               |  (610) 359-1001
+  If your life is a hard drive,     |  13 Roberts Road
+  Christ can be your backup.        |  Newtown Square, Pennsylvania

19073

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