2017-04-11 Robert Haas :
> There's a nasty trade-off here between XID consumption (and the
> aggressive vacuums it eventually causes) and preserving performance in
> the face of errors - e.g. if you make k = 100,000 you consume 100x
> fewer XIDs than if you make k = 1000, but you also have 100x th
2015-11-04 Antonin Houska :
> While prefix expression
>
> y like 'abc%'
>
> can be converted to
>
> y >= 'abc'
>
> (see expand_indexqual_opclause()), I'm not sure any kind of expansion is
> possible for '%abc%' which would result in a b-tree searchable condition.
I think the question is not about
2015-09-17 Robert Haas :
> 1. Exchange Bushy
> 2. Exchange Inter-Operator (this is what's currently implemented)
> 3. Exchange Replicate
> 4. Exchange Merge
> 5. Interchange
> 1. ?
> 2. Gather
> 3. Broadcast (sorta)
> 4. Gather Merge
> 5. Redistribute
> 1. Parallel Child
> 2. Parallel Gather
> 3
2015-09-16 Rod Taylor :
> 2015-09-15 Anastasia Lubennikova :
>
>> - We have a table tbl(f1, f2, f3, f4).
>> - We want to have an unique index on (f1,f2).
>> - We want to have an index on (f1, f2, f3) which allow us to use index for
>> complex "where" clauses.
>
> Can someone write a query where F3
2015-09-15 David Rowley :
> I'm also a bit confused where f3 comes in here. If it's UNIQUE on (f1,f2)
> and we include f4. Where's f3?
Columns f1, f2, f3 are in the internal nodes of the tree (i.e., they
are used to find the ultimate leaf nodes). f4 is only in the leaf
nodes. If f4 are typically
2015-07-24 Nicolas Barbier :
> Especially useful would be to know whether interleaving a small number
> of TID ordered streams (as would probably be generated by parallel
> scans/processing) would result in an ordering that performs
> significantly worse or not. I assume (but cannot
2015-07-23 Robert Haas :
> I think what you should do is go find out whether the second rationale
> is valid or not.
Knowing how much impact on performance such “non TID ordered” entries
have, would of course be very useful for future patch authors to know.
Especially useful would be to know whet
2015-06-05 deavid :
> Mode 3: on "aminsert", put the new entry on a second btree; leaving the
> first one untouched. Because the second btree is new, will be small, and
> writes should be faster. When doing a index scan, read tuples from both at
> same time (like merge sort). On vacuum, merge the
2015-01-05 Tom Lane :
> What would make sense to me is to teach the planner about inlining
> SQL functions that include ORDER BY clauses, so that the performance
> issue of a double sort could be avoided entirely transparently to
> the user.
Another way of getting to the point where the extra che
2014-10-18 Stephen Frost :
> * Peter Eisentraut (pete...@gmx.net) wrote:
>
>> More subtly, if we claim that a materialized view is a view, then we
>> cannot have asynchronously updated materialized views, because then we
>> have different semantics.
>
> This is, at least, a reason I can understand
2014-10-16 Stephen Frost :
> Alright, coming back to this, I have to ask- how are matviews different
> from views from the SQL standard's perspective?
Matviews that are always up to date when you access them are
semantically exactly the same as normal views. Matviews that can get
out of date, how
2014-08-07 Oleg Bartunov :
> +1 for BRIN !
+1, rolls off the tongue smoothly and captures the essence :-).
Nicolas
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To make changes to
2014-08-06 Claudio Freire :
> So, I like blockfilter a lot. I change my vote to blockfilter ;)
+1 for blockfilter, because it stresses the fact that the "physical"
arrangement of rows in blocks matters for this index.
Nicolas
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Q. Why i
2014-05-05 Bruce Momjian :
> On Mon, May 5, 2014 at 10:40:29AM -0700, Josh Berkus wrote:
>
>> * ALTER SYSTEM SET
>>
>> Lemme know if you need description text for any of the above.
>
> OK, great! Once I have the markup done, I will beef up the descriptions
> if needed and copy the text up to the
2014-04-17 Michael Paquier :
> Is there no equivalent in German? For example in French there is "ssi".
gdw (genau dann, wenn)
Nicolas
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2014-04-09 Dilip kumar :
> I would like to propose a New merge join algorithm for optimizing non ‘=’
> operators. (‘<’, ‘<=’, ‘>’, ‘>=’)
Do you have a real-world example use case of such joins, to offset the
extra planner time that will likely have to be paid (even for queries
for which the funct
2013/12/15 David Rowley :
> I've been working on speeding up aggregate functions when used in the
> context of a window's with non fixed frame heads.
> 1. Fully implement negative transition functions for SUM and AVG.
I would like to mention that this functionality is also extremely
useful to ha
2013/11/12 Simon Riggs :
> On 12 November 2013 21:41, Nicolas Barbier wrote:
>
>> Look-up speed is as follows: Each look-up must look through all
>> B-trees.
>
> That can be optimised by using a min max approach, so we need only
> look at sub-trees that may contain
2013/11/12 Claudio Freire :
> On Tue, Nov 12, 2013 at 6:41 PM, Nicolas Barbier
> wrote:
>
>> (Note that K B-trees can be merged by simply scanning all of them
>> concurrently, and merging them just like a merge sort merges runs.
>> Also, all B-trees except for the fir
2013/11/12 Nicolas Barbier :
> In conclusion, use a “B-forest” when:
>
> * The index entries are small (large fan-out).
> * The insertion throughput is high.
> * It’s OK for look-ups to be slow.
> * Extra points when the storage medium has high seek times.
Oops, forgot the m
2013/11/2 Simon Riggs :
> On 29 October 2013 16:10, Peter Geoghegan wrote:
>
>> Presumably someone will get around to implementing a btree index
>> insertion buffer one day. I think that would be a particularly
>> compelling optimization for us, because we could avoid ever inserting
>> index tupl
[ Could you please trim your citations, i.e., please don’t top-post:
https://en.wikipedia.org/wiki/Posting_style#Top-posting ]
2013/8/16 Francesco :
> Thanks for your answer.
> Yes, the client is also UTF8:
>
> MyDB=# show
> client_encoding;
> client_encoding
> -
> UTF8
> (1 row)
2013/6/27 Markus Wanner :
> On 06/27/2013 11:12 AM, Nicolas Barbier wrote:
>
>> Imagine that there are a lot of indexes, e.g., 50. Although a lookup
>> (walking one index) is equally fast, an insertion must update al 50
>> indexes. When each index requires one extra I/
2013/6/27 Nicolas Barbier :
> When each index requires one extra I/O (because each index is
> one level taller), that is 50 extra I/Os. In the partitioned case,
> each index would require the normal smaller amount of I/Os.
[..]
> Using those other indexes (both for look-ups and
&
2013/6/26 Heikki Linnakangas :
> On 26.06.2013 16:41, Yuri Levinsky wrote:
>
>> Heikki,
>> As far as I understand the height of the btree will affect the number of
>> I/Os necessary. The height of the tree does not increase linearly with
>> the number of records.
>
> Now let's compare that with a
2013/6/27 Magnus Hagander :
> Is there a particular reason why CREATE RECURSIVE VIEW is part of the
> help for CREATE VIEW, but CREATE MATERIALIZED VIEW doesn't show up
> there?
>
> I realize the technical reason (they're different man pages, and that
> also controls what's in \h in psql which is
2013/6/17 Heikki Linnakangas :
> +errmsg("concurrent refresh requires a
> unique index on just columns for all rows of the materialized view")));
Maybe my english is failing me here, but I don’t understand the “just” part.
Nicolas
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A. Because it breaks the logi
2013/5/17 Claudio Freire :
> On Fri, May 17, 2013 at 4:25 PM, Kevin Grittner wrote:
>
>>> (3) The count algorithm must be implemented in a way that understands
>>> MVCC internals: Reading the base tables must be done using a technique
>>> that reads all rows (i.e., also the ones not visible to th
2013/5/17 Kevin Grittner :
> Nicolas Barbier wrote:
>
>> Note that the basic count algorithm assumes real-serializable
>> transactions for correctness. Example:
[..]
> Good point.
>
> It might be hard to detect when this type of race condition exists,
> sin
2013/5/17 Kevin Grittner :
> During calculation of the deltas to apply to the matviews, it must
> be possible to query the referenced tables from the perspective of
> both the "before" and "after" versions of the data.
[..]
> I don't think the process applying the deltas needs to do
> anything u
2013/4/5 Noah Misch :
> On Thu, Apr 04, 2013 at 12:28:01PM +0200, Nicolas Barbier wrote:
>
>> +1. Having unlogged matviews without having incremental updates yet,
>> isn't super useful anyway.
>
> I would have surmised the opposite: since an unlogged MV requires a fu
2013/4/3 Tom Lane :
> Kevin Grittner writes:
>
>> To be honest, I don't think I've personally seen a single use case
>> for matviews where they could be used if you couldn't count on an
>> error if attempting to use them without the contents reflecting a
>> materialization of the associated query
2013/3/8 Andres Freund :
> On 2013-03-07 15:21:35 -0800, Josh Berkus wrote:
>
>> This limitation is in no way crippling for this feature, or even a major
>> detraction. I still intend to promote the heck out of this feature.
>
> Thats scaring me. Because the current state of the feature isn't
> s
2013/3/5 Kevin Grittner :
> Perhaps it would be worth looking for anything in the patch that
> you think might be painting us into a corner where it would be hard
> to do all the other cool things. While it's late enough in the
> process that changing anything like that which you find would be
>
2013/3/5 Kevin Grittner :
> Exactly. I predict that we will eventually have some special sort
> of trigger for maintaining MVs based on base table changes to
> handle the ones that are just too expensive (in developer time or
> run time) to fully automate. But there is a lot of low-hanging
> fru
2013/3/5 Robert Haas :
> All that having been said, it's hard for me to imagine that anyone
> really cares about any of this until we have an incremental update
> feature, which right now we don't. Actually, I'm betting that's going
> to be significantly harder than automatic-query-rewrite, when
2013/3/3 Kevin Grittner :
> Nicolas Barbier wrote:
>
>> I think that automatically using materialized views even when the
>> query doesn’t mention them directly, is akin to automatically
>> using indexes without having to mention them in the query. That
>> way, quer
2013/3/3 Kevin Grittner :
> Rewriting queries using
> expressions which match the MV's query to pull from the MV instead
> of the underlying tables is the exception. While that is a "sexy"
> feature, and I'm sure one can construct examples where it helps
> performance, it seems to me unlikely to
2013/2/19 Robert Haas :
> In the department of crazy ideas, what about having pg_dump NEVER
> refresh ANY materialized views?
>
> It's true that the job of pg_dump and pg_restore is to put the new
> database in the same state that the old database was in, but I think
> you could make a reasonable
2012/8/7 Kevin Grittner :
> I also think it's a problem that one can get through the entire
> "Concurrency Control" chapter (mvcc.sgml) without a clue that
> sequences aren't transactional.
It is possible to say that they *are* transactional when considering
the following definition: nextval() do
2012/5/17 Volker Grabsch :
> Also, is there any chance to include a (simple) attempt of
> such an optimiztation into PostgreSQL-9.2 beta, or is this
> only a possible topic for 9.3 and later?
For 9.2, you’re about 4 months late :-). The last commitfest was in Januari:
https://commitfest.postgres
2012/4/25 Nicolas Barbier :
> is the reason of existence for the PG-like temporary transactions.
s/transactions/tables/
Nicolas
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2012/4/25 Simon Riggs :
> So you are saying it is OK to not be able to *create* them on HS, just
> *use* pre-defined tables?
>
> That's almost useless IMHO.
>
> Applications expect to be able to do this all in the same transaction
> on one session
> CREATE TEMP TABLE x;
> ...DML commands...
> SEL
2012/4/25 Simon Riggs :
> On Wed, Apr 25, 2012 at 4:55 AM, Noah Misch wrote:
>
>> I do not see a clean behind-the-scenes fix for points 1, 4 and 5. We can
>> resolve those by adding a new variety of temporary table, one coincidentally
>> matching the SQL standard's notion of a temporary table.
2012/2/22 Robert Haas :
> On Tue, Feb 21, 2012 at 9:00 AM, Pavel Stehule
> wrote:
>
>> I had to reply to query about usage VACUUM ANALYZE or ANALYZE. I
>> expected so ANALYZE should be faster then VACUUM ANALYZE.
>>
>> But is not true. Why?
>
> I'm pretty sure that VACUUM ANALYZE *will* be faste
2012/1/4 Simon Riggs :
> On Wed, Jan 4, 2012 at 9:20 AM, Andres Freund wrote:
>
>> I wonder if CRC32c wouldn't be a good alternative given more and more cpus
>> (its in SSE 4.2) support calculating it in silicon.
>
> We're trying to get something that fits in 16bits for this release.
> I'm guessi
2011/12/30 Ants Aasma :
> On Thu, Dec 29, 2011 at 6:44 PM, Kevin Grittner
> wrote:
>
>> positives. To get this right for a checksum in the page header,
>> double-write would need to be used for all cases where
>> full_page_writes now are used (i.e., the first write of a page after
>> a checkpoin
2011/12/5 Tom Lane :
> What is bothering me is that this approach is going to cause substantial
> bloat of the executable code, and such bloat has got distributed costs,
> which we don't have any really good way to measure but for sure
> micro-benchmarks addressing only sort speed aren't going to
2011/6/29, Florian Pflug :
> Secondly, there is little point in having an type XML if we
> don't actually ensure that values of that type can only contain
> well-formed XML.
+1. The fact that XPATH() must return a type that cannot depend on the
given expression (even if it is a constant string) m
2011/6/28, Robert Haas :
> You know, it just occurred to me while reading this email that you're
> using the term "predicate lock" in a way that is totally different
> from what I learned in school. What I was taught is that the word
> "predicate" in "predicate lock" is like the word "tuple" in "
2011/6/17, Andrew Dunstan :
> On 06/17/2011 11:29 AM, Nicolas Barbier wrote:
>
>> CDATA sections are just syntactic sugar (a form of escaping):
>
> Yeah. OTOH doesn't an empty CDATA section force a child element, where a
> pure empty element does not?
Wow, some Googli
2011/6/17, Andrew Dunstan :
> On 06/17/2011 10:55 AM, Radosław Smogura wrote:
>
>> XML canonization preservs whitespaces, if I remember
>> well, I think there is example.
>>
>> In any case if I will store image in XML (I've seen this), preservation of
>> white spaces and new lines is important.
>
2011/5/31, Tom Lane :
> Unless maybe there's a kFreeBSD-like project out there with NetBSD as
> the kernel?)
There used to be an attempt by Debian (called GNU/NetBSD), but that
has since long been abandoned. I don't know of any other similar
projects.
http://www.debian.org/ports/netbsd/>
Wikipe
2011/5/30, Nick Raj :
> 3. When tuples are 5 lakh
For the benefit of the others: "5 lakh" seems to mean 500,000.
http://en.wikipedia.org/wiki/Lakh>
Nicolas
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Q. Why is top posting bad?
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[ Forgot the list. ]
2011/5/12, Yves Weißig :
> I'm currently debugging my developed AM and are running into this problem:
>
> TRAP: FailedAssertion("!(((bool) (((void*)(tid) != ((void *)0)) &&
> ((tid)->ip_posid != 0", File: "indexam.c", Line: 488)
>
> Can anybody explain what it means? I'm
2011/5/11, Bruce Momjian :
> FYI, because the visibility map is only one _bit_ per page, it is 8000 *
> 8 or 64k times smaller than the heap, e.g. one 8k page covers 64MB of
> heap pages.
Actually, that would be "one 8kB block covers 512MB of heap": 1 block
of visibility map (8kB) = 64k visibilit
2011/4/27 Vlad Arkhipov :
> I'm currently need predicate locking in the project, so there are two ways
> to get it by now: implement it by creating special database records to lock
> with SELECT FOR UPDATE or wait while they will be implemented in Postgres
> core. Is there something like predicate
2011/3/30 aaronenabs :
> Can you alos advise how i change the the HeapTupleSatisfiesVisibility() to
> true within the source code:
[..]
> #define HeapTupleSatisfiesVisibility(tuple, snapshot, buffer) \
> ((*(snapshot)->satisfies) ((tuple)->t_data, snapshot, buffer))
As someone totally no
2011/3/30 aaronenabs :
> Hi all i have been trying to compile the sourcecode for postgresql but keep
> getting an error message when running it in cygwin.
>
> it states:
>
> dllwrap: gcc exited with status 1
> make[3]: *** [cygpq.dll] Error 1
> make[3]: Leaving directory
> `/postgresql-9.0.3/postg
2011/3/20 hom :
> I trace into scan.c because I want to known how the paser tree is
> built and I debug the source step by step.
I suggest you learn how flex/bison work first. The contents of the *.c
files generated by flex/bison are not generally supposed to be
interpreted by humans, rather you
2011/3/15 Dmitriy Igrishin :
> Oleg Bartunov and I intend to begin the project of translation
> of PostgreSQL documentation on Russian.
Just to make sure that you are aware of a recently-started effort to
create a German translation, by Susanne and others:
http://archives.postgresql.org/pgsql-ha
2011/3/10 Jesper Krogh :
> On 2011-03-10 19:25, Bruce Momjian wrote:
>
>> Sure, anyone can add text to that wiki; you create a community account
>> here:
>>
>> http://www.postgresql.org/community/signup
>
> Suggestion: Add this url to the login box on the wiki.
+1, Adrian von Bidder had t
2011/3/9 Nicolas Barbier :
> Note that the standard defines things that must never happen in the
> case of READ COMMITTED, it does not specify that one *must* be able to
> see the stuff as committed by previous transactions, for example.
Hmm, make that "stuff as committed
2011/3/9 Vlad Arkhipov :
> Let there are two transactions that were created with read commited
> isolation level. In the first one we're executing a SELECT query:
> SELECT * FROM t UNION ALL SELECT * FROM t;
>
> In the second transaction we're modifying the same table:
> INSERT INTO t DEFAULT VALU
2011/3/1 Andrew Dunstan :
> I think hierarchical data really only scratches the surface of the problem.
> It would be nice to be able to specify all sorts of context for searches:
>
> * foo after bar
> * foo near bar
> * foo and bar in the same paragraph
> * foo as a parent/child/ancestor/
2011/2/11 Kevin Grittner :
> "mac_man2...@yahoo.it" wrote:
>
>> I need to know, from an algorithmic point of view, in which cases
>> sorting is invoked.
[..]
> Are your really looking to categorize the types of queries where
> sorting is *invoked*, or the ones where it is *considered*? Or
> pe
[ Please don't top-post. http://en.wikipedia.org/wiki/Posting_style> ]
2011/2/11 mac_man2...@yahoo.it :
> So, is there any precise way to discover when sorting is invoked?
EXPLAIN shows how a query would be executed; explicit sorts should be
mostly obvious.
http://www.postgresql.org/docs/9.0/sta
2011/2/10 mac_man2...@yahoo.it :
> Which operations invoke the sorting algorithms implemented in the sorting
> module (tuplesort.c) ?
> Of course, one of those operations invoking sorting is the ORDER BY clause
> and the DISTINCT too.
>
> Moreover, the Merge Join should be implemented invoking sor
2011/2/9 amit sehas :
> Lets say that the cost based optimizer determines that the order of the
> joins should be T1.a=T2.b followed by T2.c = T3.d followed by T3.e = T4.f
>
> the question we have is during query execution are the joins evaluated
> completely one by one in that order, or the fir
2011/2/1 Magnus Hagander :
> On Tue, Feb 1, 2011 at 07:56, Pavel Stehule wrote:
>
>> 2011/2/1 Magnus Hagander :
>>
>>> On Tue, Feb 1, 2011 at 05:53, Pavel Stehule wrote:
>>>
Hello
There are broken links inside messages from commiters.
projects /
404 - No s
2011/1/27 Bruce Momjian :
> Bruce Momjian wrote:
>
>> Peter Eisentraut wrote:
>>
>>> We use small "k" in postgresql.conf, so pg_test_fsync should use the
>>> same. Using "kB" would be more accurate in any case.
>>
>> OK, done with the attached applied patch.
>
> FYI, I had used 'k' because this p
2011/1/21 Robert Haas :
> On Fri, Jan 21, 2011 at 8:05 AM, Nicolas Barbier
> wrote:
>
>> 2011/1/21 Anssi Kääriäinen :
>>
>>> Sorry for bothering all of you, but I just don't get this. What if T2 rolls
>>> back instead of committing? Then the snapshot
2011/1/21 Anssi Kääriäinen :
> Sorry for bothering all of you, but I just don't get this. What if T2 rolls
> back instead of committing? Then the snapshot of T3 would have been valid,
> right? Now, for the snapshot of T3 it doesn't matter if T2 commits or if it
> doesn't, because it can't see the
2011/1/16 Simone Aiken :
> is there a way to make queries on the system tables show me what
> is actually there when I'm poking around? So for example:
>
> Select * from pg_type limit 1;
>
> tells me that the typoutput is 'boolout'. An english string rather
>
2011/1/5 Zotov :
> Why doesn`t work this query?
> select table1.field1, func1.field2 from table1 left outer join
> func1(table1.field1) on true where func1.field3 in (20, 100);
>
> If i have other than LEFT OUTER JOIN I can understand why
> ERROR: invalid reference to FROM-clause entry for tabl
2010/12/24 Florian Pflug :
> On Dec23, 2010, at 20:39 , Tomas Vondra wrote:
>
>> I guess we could use the highest possible value (equal to the number
>> of tuples) - according to wiki you need about 10 bits per element
>> with 1% error, i.e. about 10MB of memory for each million of
>> elem
2010/12/20 Martijn van Oosterhout :
> On Mon, Dec 20, 2010 at 09:03:56AM +0900, Itagaki Takahiro wrote:
>
>> UTF-8 is not a superset of all encodings.
>
> I think you mean Unicode is not a superset of all character sets. I've
> heard this before but never found what's missing. [citation needed]?
2010/12/16 Robert Haas :
> On Thu, Dec 16, 2010 at 7:49 AM, Dimitri Fontaine
> wrote:
>
>> Please note that the SQL scripts seem to be encoded in latin9.
>
> Seems like an odd choice. Why not UTF-8?
Latin 9 = ISO 8859-15 = a more modern version of Latin 1 (ISO 8859-1),
which includes the € sym
2010/12/15 matteo durighetto :
> But why we need all these versions of the same row on table, if for
> rollback we need only the original row X (X0) ?
And the "previous" value of row X during the execution of a statement
(because statements don't see their own changes, think INSERT INTO a
SELECT
2010/12/13 Tom Lane :
> But allow me to harbor doubts that they really
> intend to allow someone to force a constraint to be considered valid
> without any verification.
"Table constraints are either enforced or not enforced. Domain
constraints and assertions are always enforced.", 4.17.2
I don'
2010/11/11 David E. Wheeler :
> On Nov 11, 2010, at 10:05 AM, Tom Lane wrote:
>
>>> So are you planning to implement multisets? It's a feature I'd love to see
>>
>> What actual functionality does it buy? AFAICT from Itagaki-san's
>> description, it's an array only you ignore the specific element
2010/11/2 Kenneth Marshall :
> Given that our hash implimentation mixes the input data well (It does.
> I tested it.) then a simple rotate-and-xor method is all that should
> be needed to maintain all of the needed information. The original
> hash function has done the heavy lifting in this case.
2010/9/27 Robert Haas :
> On Mon, Sep 27, 2010 at 12:56 PM, Guillaume Du Pasquier
> wrote:
>
>> Our client runs on the same machine as the postgresql server.
>> Would it be possible to use PF_UNIX sockets ?
>
> Yeah, actually that's the default, if you just run "psql" with no
> parameters. It lo
2010/9/27 Guillaume Du Pasquier :
> In both cases, the client socket (pgadmin or my program) remains in
> TIME_WAIT state.
>
> I have used wireshark to sniff the TCP protocol.
>
> We have at the end of a connection:
>
> Client Server
>
> ---> FIN,ACK --->
> <--- FIN,A
[ Forgot the list, resending. ]
2010/9/25 Greg Stark :
> On Thu, Sep 23, 2010 at 4:08 PM, Kevin Grittner
> wrote:
>
>> One place I'm particularly interested in using such a feature is in
>> pg_dump. Without it we have the choice of using a SERIALIZABLE
>> transaction, which might fail or cause f
2010/8/25 Simon Riggs :
> On Wed, 2010-08-25 at 16:14 +0200, Nicolas Barbier wrote:
>> 2010/8/25 Simon Riggs :
>>
>> > "referenced" meaning "by an RI constraint", which only ever refers to
>> > PKs in other tables.
>>
>> FK constr
2010/8/25 Simon Riggs :
> "referenced" meaning "by an RI constraint", which only ever refers to
> PKs in other tables.
FK constraints can also point to non-PK UNIQUE columns.
Nicolas
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htt
2010/8/24 Pei He :
> I want to run two different versions of postgresql-8.2.5 under eclipse.
>
> But, it requires me to change PGDATA and LD_LIBRARY_PATH to switch.
>
> Moreover, to let eclipse know the changes, I need to modify .profile
> under my home folder, and log out and log in. (I am using
2010/8/11 Marko Tiikkaja :
> On 8/11/10 8:31 AM +0300, Peter Eisentraut wrote:
>
>> Thinking about SQL assertions (check constraints that are independent of
>> one particular table), do you think it would be reasonable to implement
>> those on top of constraint triggers? On creation you'd hook up
2010/8/5 Richard :
> All jods are done by client code, not manually.
What is a jod?
> I still did't not understand what you said.
> What break what?
The fact that you replaced CHECKPOINT_WAIT with CHECKPOINT_IMMEDIATE
is the cause of your problem. You "broke" the correctness of the
system by do
2010/6/30 Robert Haas :
> By the way, does the SQL standard say anything about materialized views?
AFAIK, nope. Probably for the same reason that indexes are not
mentioned by the standard: both are only performance enhancements, and
one could easily imagine future SQL database systems that manage
2010/5/25 Florian Pflug :
> Hm, but for there to be an actual problem (and not a false positive), an
> actual dangerous circle has to exist in the dependency graph. The
> existence of a dangerous structure is just a necessary (but not
> sufficient) and easily checked-for condition for that, right?
2010/5/25 Florian Pflug :
> On May 25, 2010, at 20:18 , Dan Ports wrote:
>
>> T3, which is a read-only transaction, sees the incremented date and an
>> empty list of receipts. But T1 later commits a new entry in the
>> receipts table with the old date. No serializable ordering allows this.
>>
>> H
2010/5/25 Dan Ports :
> On Tue, May 25, 2010 at 02:00:42PM +0200, Nicolas Barbier wrote:
>
>> I don't understand the problem. According to me, in the context of
>> SSI, a read-only slave can just map SERIALIZABLE to the technical
>> implementation of REPEATABLE READ
2010/5/25 Dan Ports :
> On Mon, May 24, 2010 at 10:24:07AM -0500, Kevin Grittner wrote:
>
>> Replicating or recreating the whole predicate locking and conflict
>> detection on slaves is not feasible for performance reasons. (I
>> won't elaborate unless someone feels that's not intuitively
>> obvio
2010/5/14 Greg Stark :
> On Thu, May 13, 2010 at 10:25 PM, Florian Pflug wrote:
>
>> C1: BEGIN
>> C1: SELECT * FROM t WHERE id = 1 FOR UPDATE
>> C2: BEGIN
>> C2: SET TRANSACTION ISOLATION LEVEL SERIALIZABLE
>> C2: SELECT * FROM t -- Take snapshot before C1 commits
>> C1: COMMIT
>> C2: DELETE FROM
2010/5/11 Marko Tiikkaja :
> This is getting way off topic, but:
>
> On 5/11/10 3:55 PM +0300, Nicolas Barbier wrote:
>>
>> T2> SELECT i FROM a WHERE i = 1 FOR SHARE; -- Lock a with i = 1 FOR
>> SHARE.
>> i
>> ---
>> 1
>> (1 Zeile)
>>
2010/5/11 Marko Tiikkaja :
> On 2010-05-11 14:29 +0200, Robert Haas wrote:
>
>> On Tue, May 11, 2010 at 2:16 AM, Dmitry Fefelov wrote:
>>
The referential integrity triggers contain some extra magic that isn't
easily simulatable in userland, and that is necessary to make the
foreign
2010/4/7 Olivier Baheux :
> i'm trying to find where are stored sequence definition
> (increment,minvalue,maxvalue,start,cache) in system tables. Atm I
> found everything exept sequence.
It's in the sequence itself (which can be accessed like a table). The
fact that this "table" is in fact a sequ
2010/3/23 Pavel Stehule :
> 2010/3/23 Takahiro Itagaki :
>
>> The fundamental issue seems to be in the slow initialization of
>> dictionaries. If so, how about adding a pre-complile tool to convert
>> a dictionary into a binary file, and each backend simply mmap it?
>
> It means loading about 25MB
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