[GENERAL] disable seqscan
Hi, I have build an index. When, i execute the query, it gives the result by sequential scan, not by using my index. I have already run vacuum analyze to collect some statistics regarding table. May be sequential scan is giving faster execution time than my indexing. But i want to know how much time it would take in my indexing. For that, i have set enable_seqscan=off in postgresql.conf. But it still going through sequential scan. Even i tried to set for a particular session, by set enable_seqscan=off on psql terminal. It again going by sequential scan. Does any one having an idea to force postgres to use index scan? Thanks Nick
Re: [GENERAL] disable seqscan
On Mon, May 23, 2011 at 05:31:04PM +0530, Nick Raj wrote: Hi, I have build an index. When, i execute the query, it gives the result by sequential scan, not by using my index. For that, i have set enable_seqscan=off in postgresql.conf. But it still going through sequential scan. It sounds like your index can't actually be used to satisfy your query. Without seeing the table definition, index definition, and query, however, it's pretty hard to give you a real answer. A -- Andrew Sullivan a...@crankycanuck.ca -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] disable seqscan
Andrew Sullivan a...@crankycanuck.ca wrote: On Mon, May 23, 2011 at 05:31:04PM +0530, Nick Raj wrote: Hi, I have build an index. When, i execute the query, it gives the result by sequential scan, not by using my index. For that, i have set enable_seqscan=off in postgresql.conf. But it still going through sequential scan. It sounds like your index can't actually be used to satisfy your query. Without seeing the table definition, index definition, and query, however, it's pretty hard to give you a real answer. ... and the output produced by explain analyse insert your query Andreas -- Really, I'm not out to destroy Microsoft. That will just be a completely unintentional side effect. (Linus Torvalds) If I was god, I would recompile penguin with --enable-fly. (unknown) Kaufbach, Saxony, Germany, Europe. N 51.05082°, E 13.56889° -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] disable seqscan
On Mon, May 23, 2011 at 5:44 PM, Andreas Kretschmer
akretsch...@spamfence.net wrote:
Andrew Sullivan a...@crankycanuck.ca wrote:
On Mon, May 23, 2011 at 05:31:04PM +0530, Nick Raj wrote:
Hi,
I have build an index. When, i execute the query, it gives the result
by
sequential scan, not by using my index.
For that, i have set enable_seqscan=off in postgresql.conf. But it
still
going through sequential scan.
It sounds like your index can't actually be used to satisfy your
query. Without seeing the table definition, index definition, and
query, however, it's pretty hard to give you a real answer.
... and the output produced by
explain analyse insert your query
Explain analyze of my query
explain analyze select * from vehicle_stindex where
ndpoint_overlap('(116.4,39.3,2008/02/11 11:11:11),(117.8,39.98,2008/02/13
11:11:11)',stpoint);
QUERY
PLAN
--
Seq Scan on vehicle_stindex (cost=100.00..1050870.86
rows=698823 width=66) (actual time=3285.106..3285.106 rows=0 loops=1)
Filter: ndpoint_overlap('(116.40,39.30,2008-02-11
11:11:11+05:30),(117.80,39.98,2008-02-13 11:11:11+05:30)'::ndpoint,
stpoint)
Total runtime: 3285.153 ms
(3 rows)
Table Defination
Table public.vehicle_stindex
Column | Type | Modifiers
-+-+---
regno | text|
stpoint | ndpoint |
Indexes:
stindex gist (stpoint)
It has 2099192 tuples.
Index defination
create index stindex on vehicle_stindex using gist(stpoint).
I have defined a datatype called ndpoint. It works same as contrib/cube
code (cube datatype).
Query is working fine. I mean no error from query or my datatype. All are
giving right result.
If anything more to mention, then tell me
Nick
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Re: [GENERAL] disable seqscan
Nick Raj nickrajj...@gmail.com wrote:
On Mon, May 23, 2011 at 5:44 PM, Andreas Kretschmer
akretsch...@spamfence.net
wrote:
Andrew Sullivan a...@crankycanuck.ca wrote:
On Mon, May 23, 2011 at 05:31:04PM +0530, Nick Raj wrote:
Hi,
I have build an index. When, i execute the query, it gives the result
by
sequential scan, not by using my index.
For that, i have set enable_seqscan=off in postgresql.conf. But it
still
going through sequential scan.
It sounds like your index can't actually be used to satisfy your
query. Without seeing the table definition, index definition, and
query, however, it's pretty hard to give you a real answer.
... and the output produced by
explain analyse insert your query
Explain analyze of my query
explain analyze select * from vehicle_stindex where ndpoint_overlap('
(116.4,39.3,2008/02/11 11:11:11),(117.8,39.98,2008/02/13 11:11:11)
',stpoint);
QUERY
PLAN
--
Seq Scan on vehicle_stindex (cost=100.00..1050870.86 rows=
698823 width=66) (actual time=3285.106..3285.106 rows=0 loops=1)
Filter: ndpoint_overlap('(116.40,39.30,2008-02-11
11:11:11+05:30),(117.80,39.98,2008-02-13
11:11:11+05:30)'::ndpoint,
stpoint)
Total runtime: 3285.153 ms
(3 rows)
Table Defination
Table public.vehicle_stindex
Column | Type | Modifiers
-+-+---
regno | text|
stpoint | ndpoint |
Indexes:
stindex gist (stpoint)
It has 2099192 tuples.
Index defination
create index stindex on vehicle_stindex using gist(stpoint).
I have defined a datatype called ndpoint. It works same as contrib/cube
code (cube datatype).
Query is working fine. I mean no error from query or my datatype. All are
giving right result.
If anything more to mention, then tell me
Okay. Sorry, i'm not familiar with gist and gist-functions and postgis
and so on, but i think, your index is unuseable in this case.
To use the index you have to build a functional index with this
function, for instance (i'm not sure if this is correct, as i said, i'm
not familiar with this):
create index stindex on vehicle_stindex (ndpoint_overlap(...))
Simple example for an functional index:
test=# create table foo (f text);
CREATE TABLE
Time: 5,555 ms
test=*# create index idx_foo on foo(md5(f));
CREATE INDEX
now you have an index on the md5-sum from foo.f, and you can say:
select * from foo where md5(f) = md5('test')
I think, that's the way you are looking for.
Andreas
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[GENERAL] Postgres 8.3.5 - ECPG and the use of descriptors and cursors in multi-threaded programs
Hello Guys,
In a multi-threaded server program using Postgresql 8.3.5 with ECPG
interface for C, we have problems using descriptors (and possibly cursors).
We have created a common database interface module with basically 1
function: SQLExec(). In the 'select' part of this function we (statically)
allocate a descriptor as shown below.
This seems to be working most of the time, but looking at the generated C
code from the ecpg compiler and the associated library functions, we are not
sure whether we should put mutex locks around the 'select' part to avoid
several threads are using the same execdesc at the same time.
We have made sure that each thread uses their own and only their own
database connection, but are unsure whether the ecpg library functions is able
to handle multiple use of the statical name execdesc ?
static int SQLExec( const char *thisDbConn, char *paramStmt )
{
EXEC SQL BEGIN DECLARE SECTION;
const char *_thisDbConn = thisDbConn;
char *stmt = paramStmt;
EXEC SQL END DECLARE SECTION;
.
.
if( select ) {
.
.
EXEC SQL AT :_thisDbConn ALLOCATE DESCRIPTOR execdesc; line = __LINE__;
EXEC SQL AT :_thisDbConn PREPARE execquery FROM :stmt; line = __LINE__;
EXEC SQL AT :_thisDbConn DECLARE execcurs CURSOR FOR execquery; line =
__LINE__;
EXEC SQL AT :_thisDbConn OPEN execcurs; line = __LINE__;
while( ok ) {
EXEC SQL AT :_thisDbConn FETCH IN execcurs INTO SQL DESCRIPTOR execdesc;
.
(handle data per row, using execdesc)
.
}
.
(deallocation of stuff)
.
}
}
We experience spurious crashes with SIGSEGV and tracebacks of the core dump
usually ends within some ecpg library function, hence this question.
Please help,
Leif
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Re: [GENERAL] Where are plpy.execute python commands issued?
On 05/23/2011 06:44 AM, Michael McInnis wrote: I've seen numerous references to this syntax but haven't found where you issue the command. Tried it in a testpython.py file, no luck. Can't find a plpy file anywhere. I know it's going to be simple but need help. rv = plpy.execute(SELECT * FROM my_table, 5) Thanks Michael McInnis 6033 44th Ave. N.E. Seattle, WA 98115 206 517-4701 You have to run it as a plpythonu function as in: create function test() returns int as $$ rv=plpy.execute(SELECT * FROM my_table, 5) for row in rv: do something return 1 $$ langauge 'plpythonu';
Re: [GENERAL] disable seqscan
Nick Raj nickrajj...@gmail.com writes:
Andrew Sullivan a...@crankycanuck.ca wrote:
It sounds like your index can't actually be used to satisfy your
query. Without seeing the table definition, index definition, and
query, however, it's pretty hard to give you a real answer.
explain analyze select * from vehicle_stindex where
ndpoint_overlap('(116.4,39.3,2008/02/11 11:11:11),(117.8,39.98,2008/02/13
11:11:11)',stpoint);
I have defined a datatype called ndpoint. It works same as contrib/cube
code (cube datatype).
Indexes can only be used with WHERE conditions that are of the form
indexed_column operator some_expression
where the operator is one of those belonging to the index's operator
class. You haven't told us what operators you put into the operator
class for this new data type, but in any case the function
ndpoint_overlap is not one of them.
regards, tom lane
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[GENERAL] Using right() in a view
Hi all,
please foregive me for this rather trivial question, but I´ve worked in it
for quite som time and could use som help now. :)
I have a table where it want to create a idkey using our municipality number
+ the road number + the housenumber.
The municipality and housenumber is in a fixed size, so they are okay. But
the road number differs from two digits up to four. I was then thinking
about doing something like this:
CREATE OR REPLACE VIEW test AS
SELECT
right(cast('000' as text) || cast(road_number as text), 4) AS GEO_ADRESSE
FROM rk_ois.bbrbygning
WHERE ejerlav 0
to ensure that the road_number would be a fixed size (four digitis).
Unfortunately this doesn't work.
Any idea on how to solve this?
Christian
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[GENERAL] Postgre Client only install on Linux- 8.4.7
Hi, How can i install only the postgre client on an RHEL 5.5 machine?? I have installed the server running the ./postgresql-8.4.7-1-linux-x64.bin command. Any help appreciated... Thanks Chitra
[GENERAL] Postgre Client only Install on Linux- 8.4.7
Hi, How can i install only the postgre client on an RHEL 5.5 machine?? I have installed the server running the ./postgresql-8.4.7-1-linux-x64.bin command. Any help appreciated... Thanks Chitra
Re: [GENERAL] Using right() in a view
Chrishelring wrote:
CREATE OR REPLACE VIEW test AS
SELECT
right(cast('000' as text) || cast(road_number as text), 4) AS GEO_ADRESSE
FROM rk_ois.bbrbygning
WHERE ejerlav 0
to ensure that the road_number would be a fixed size (four digitis).
Unfortunately this doesn't work.
Try using:
select to_char(road_number, 'FM') as GEO_ADRESSE
HTH
Bosco.
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Re: [GENERAL] Postgres 8.3.5 - ECPG and the use of descriptors and cursors in multi-threaded programs
Leif Jensen wrote: This seems to be working most of the time, but looking at the generated C code from the ecpg compiler and the associated library functions, we are not sure whether we should put mutex locks around the 'select' part to avoid several threads are using the same execdesc at the same time. We have made sure that each thread uses their own and only their own database connection, but are unsure whether the ecpg library functions is able to handle multiple use of the statical name execdesc ? You are most probably trashing memory by using the same descriptor name in multiple threads. However, given that you have already spent the effort to have the connections 'thread-dedicated' I think that rather than creating a critical path through an area that is intentionally supposed to be mutli- hreaded, I'd be inclined to use the connection name (or some derivation of it) as the name of the descriptor. I haven't used descriptors in ecpg so I don't know if the syntax works, but you could try: exec sql char *dname = _thisDbConn; // Or some derivation EXEC SQL AT :_thisDbConn ALLOCATE DESCRIPTOR :dname; ... EXEC SQL AT :_thisDbConn FETCH IN execcurs INTO SQL DESCRIPTOR :dname; ... EXEC SQL DEALLOCATE DESCRIPTOR :dname; Just a thought. Bosco. -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] Postgre Client only Install on Linux- 8.4.7
On 05/23/11 5:16 AM, Chitra wrote: How can i install only the postgre client on an RHEL 5.5 machine?? I have installed the server running the ./postgresql-8.4.7-1-linux-x64.bin command. use the rpms from the yum repository, postgresql-libs is the runtime client software. see http://yum.pgrpms.org/ and http://yum.pgrpms.org/howtoyum.php frankly, I would use that version for the server too, rather than that .bin thing -- john r pierceN 37, W 123 santa cruz ca mid-left coast -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] Trapping errors
UPDATE tbl SET score = divide_double_default(score, s, 1e-200) ... UPDATE tbl SET score = multiply_double_default(score, s, 9) ... Code the divide_double_default/multiply_double_default functions with error handling that will return the desired value (either zero or the supplied parameter) if an exception is thrown; probably with a WARNING/NOTICE raised as well. David J. -Original Message- From: pgsql-general-ow...@postgresql.org [mailto:pgsql-general- ow...@postgresql.org] On Behalf Of Shane W Sent: Monday, May 23, 2011 4:08 PM To: pgsql-general@postgresql.org Subject: [GENERAL] Trapping errors Hello list, I have a table with double precision columns and update queries which multiply and divide these values. I am wondering if it's possible to catch overflow and underflow errors to set the column to 0 in the case of an underflow and a large value in the case of an overflow. Currently, I have an exception handler in a PLPGSQL ufunction that sort of does this. begin update tbl set score = score/s exception when numeric_value_out_of range then update tbl set score=0 where cast(score/s as numeric) 1e-200 end; But this is messy since the exception needs to rescan the entire table if even one row fails the update. Is there a better way to do this? Best, Shane -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] strange behaviour in 9.0.2 / ERROR: 22003: value out of range: overflow
On 20 Mai, 22:55, rudi rudi.stras...@gmail.com wrote:
Hi all,
I feel like I hit a bug in postgres 9.0.2 with a query like this
(there's actually a quite complicated view hidden behind), however
note
the 'IN' selection contains two identical keys. When I execute a
similar query without the duplicate, the query returns, so I would
conclude it shoud be a bug.
This query fails as you can tell from the output:
mydb=# select * from cpcpk_by_lot where foundry='x' and lot='valerie'
and epclass='wac' and area='device' and parameter in
('RVT_2P_NOM_1UX5_N_VTSAT','RVT_2P_NOM_1UX5_N_VTSAT');
ERROR: 22003: value out of range: overflow
LOCATION: float4mul, float.c:750
while the a practically identical query returns with the expected
result?
mydb=# select * from cpcpk_by_lot where foundry='x' and lot='valerie'
and epclass='wac' and area='device' and parameter in
('RVT_2P_NOM_1UX5_N_VTSAT');
I hope anyone can give me a hint how to proceed
Best regards,
Rudi
I found out that the issues is caused by overflows in floating point
(REAL) operation. After some additional debug info using VERBOSITY
that became more or less evident. I wonder whether the behaviour can
be optimized, such that the individual value can be set to 'nan'
instead of causing a fail for the entire query. In a productive
environment this would scare the hell out of me.
In case someone has ideas how such conditions can be avoided, please
forward me some hints. I tend to believe that there must be a better
soluation than the one which is currently in place.
Best regards,
Rudi
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[GENERAL] Postgres questions
Hi, I have Debian Lenny server with Postgres 8.3 that is workin correctly, but I have some questions about this installation. This server is working whitout any problem but it is a little critical and I need to know how can I do... - I need to connect from postgres to other database (linked server) no postgres (for example with jdbc or odbc). I have tried to work with dbi-link with sql, it seems to work but with poor performance and whit other database different mssql is not working. What possible options exsits with 8.3? and with other versions? - This server has some critical applications and I need high availability, but I'm not sure about possible options for this versions or similar. I have thought about active/active, active/passive or active/read-only but I'm not sure what are real options, and what could be a possible environment for this situation Thanks
Re: [GENERAL] Postgres questions
On 24/05/2011 6:10 AM, Trenta sis wrote: - I need to connect from postgres to other database (linked server) no postgres (for example with jdbc or odbc). I have tried to work with dbi-link with sql, it seems to work but with poor performance and whit other database different mssql is not working. What possible options exsits with 8.3? and with other versions? DBI-link is probably your best bet. Another possibility is to use an in-database procedural language to talk to the other database - for example, PL/perl via DBI::DBD or PL/Python via a PEP-249 (http://www.python.org/dev/peps/pep-0249/) database driver like pymssql. Otherwise you can do the data sharing/sync/whatever via a client application that has connections to PostgreSQL and to the other database of interest. That's often a better choice for more complex jobs. Perhaps it'd help if you explained why you need this and what you want to accomplish with it? - This server has some critical applications and I need high availability, but I'm not sure about possible options for this versions or similar. I have thought about active/active, active/passive or active/read-only but I'm not sure what are real options, and what could be a possible environment for this situation It depends a LOT on what your needs are, and what your budget is. You have some basic questions to ask yourself, like: - Do I need true HA with failover, or just to protect against data loss? - Can I modify my apps to be aware of failover, or does failover have to be transparent? - Do I need multi-site failover or is all access of interest within one site? - What kind of guarantees do I need about data loss windows at failover time? Can I afford to lose the last x transactions / seconds worth of transactions? Or must absolutely every transaction be retained at all costs? Once you've worked out the answers to those kinds of questions, THEN you can look at bucardo, slony-I, PostgreSQL 9.0 native replication, etc etc as well as failover-control options like heartbeat and decide what might be suitable for you. -- Craig Ringer Tech-related writing at http://soapyfrogs.blogspot.com/ -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
[GENERAL] PostgreSQL and SSIS
I have an Microsoft SQL Server IS job that has been running in production for several years. It pulls data from a PostgreSQL 8.4.2 database on Linux into an SQL Server 2005 installation on Windows Server 2003 (all 32-bit). I am re-writing this in a test environment that consists of the same PostgreSQL database and an SQL Server 2008R2 installation on Windows Server 2008R2 (all 64-bit). On the Windows Server 2008R2 machine, I installed 64 bit Postgres ODBC drivers and found that I could not see them when creating an ADO.net connection manager in BIDS. A bit of googling later, I removed the 64 bit drivers and installed 32-bit Postgres ODBC drivers and set up DSNs usning windows\SysWOW64\odbcad32.exe. When setting up the DSNs, clicking the test button returned 'Connection successful'. Back to BIDS, create a new ADO.net connection manager, ODBC Data Provider, select the DSN name in 'Use user or system data source name', hit the test connection button. It returns 'Test connection succeeded'. Create a data flow task, edit, add an ADO.NET source, edit, select the new connection manager, Data access mode is set to 'Table or view', click the drop down for 'Name of the table or view:', it says loading and will sit there like that forever. If I click it again, it returns the following error message: 'Could not retrieve the table information for the connection manager 'PostgreSQL30'. Object reference not set to an instance of an object. (Microsoft.DataWarehouse)' If I select 'SQL Command' as the Data Access mode, and enter any SQL Command (eg select * from PostgresTable) and hit the Preview button, the expected data is returned. My question is why can it not return the list of tables, but it can return data. Any help would be appreciated. Rick Bailey Database Specialist Materials Research Institute 123 Land Water Building University Park, PA 16802 814-863-1294
Re: [GENERAL] how to start a procedure after postgresql started.
2011/5/23 Craig Ringer cr...@postnewspapers.com.au: On 23/05/2011 10:13 AM, jun yang wrote: actually, we will write the procedure in pl/python,then fork a new thread or a new process which is easy. Yikes. Be careful there - it's not as easy as you think it is. Spawning a new thread within a PostgreSQL backend is a very, very, very bad idea unless you know EXACTLY what you are doing. Do not do it if there is any alternative. As for spawning a new process: a PostgreSQL backend's environment isn't guaranteed to be what you expect. I don't just mean environment variables. The most likely surprise will be finding yourself running in quite a limiting SELinux context if SELinux is present, but I'm sure there are more possible quirks. Also, on unix/linux, if the backend process that invoked your helper dies, your helper will be re-parented to init not to the postmaster, which won't be what you expected. thanks for the info,i am just not have such deep learn of pg internal, i am on user level,not hacker,so the mail is in pgsql-general,not hacker list. There's been discussion of adding the ability for the postmaster to start helper daemons, and if that were merged you could use a helper started alongside the postmaster to do the work. Right now, though, you're better off doing things how PgAgent etc do it, that is out-of-process via a regular Pg connection. then the one sitting between pg and borker is a helper daemon,it is great,more info about that? PgAgent is nice,i am just wondering why it can't be integrated in standard pg install,cause security? functionality? Doing just that is sometimes discussed, and I think it'll happen eventually. First, though, PostgreSQL's postmaster needs to be altered so that it can start and manage helper programs and daemons. As of now, that hasn't happened yet, or at least nobody has written a good enough patch that the core team have been willing to accept it. if helper daemon integrated in pg,the PgAgent can be a helper daemon too. i'd like helper daemon can operate like windows service,you can disable it,make it mannual start, or auto start with pg. Your best bet at the moment is to integrate with operating system service mechanisms. On Windows, use services. On UNIX/Linux, use the init system. On Mac OS X, use launchd. Part of the reason the postmaster hasn't been altered to support managing daemons is because some people (understandably) think that that's the OS's job, and not something PostgreSQL should duplicate. well,from user viewpoint,i prefer that pg bundle with such function,like extension in pg,the function default is disable.make it easier for those who need it will be a promotion for pg. many commercial db production include such a schedule function, not only for making money,there is user need in practice. In an ideal world I'd agree with them, but the current computing world is far from ideal. Every OS is annoyingly different in how it manages daemons, and many init systems are painfully limited in terms of the kind of events they can handle. Most can't even handle If service x exits, do y. Monitoring capabilities and the like must be individually provided by each service if they want to be even a little bit portable. Nonetheless, I think that's your best bet right now. yes,it is so complicated for a common user to do such things. -- Craig Ringer Tech-related writing at http://soapyfrogs.blogspot.com/ -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] how to start a procedure after postgresql started.
On May 23, 2011, at 9:46 PM, jun yang wrote: thanks for the info,i am just not have such deep learn of pg internal, i am on user level,not hacker,so the mail is in pgsql-general,not hacker list. What you are asking to do is not a typical user function. It would be more appropriate for a hacker list. -- Rick Genter rick.gen...@gmail.com -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] how to start a procedure after postgresql started.
On 24/05/11 12:46, jun yang wrote: thanks for the info,i am just not have such deep learn of pg internal, i am on user level,not hacker,so the mail is in pgsql-general,not hacker list. Then you really, really, REALLY don't want to start a thread within the backend, and should avoid spawning processes from backends too. To get either approach right will require a much deeper understanding of how Pg works. Part of the reason the postmaster hasn't been altered to support managing daemons is because some people (understandably) think that that's the OS's job, and not something PostgreSQL should duplicate. well,from user viewpoint,i prefer that pg bundle with such function,like extension in pg,the function default is disable.make it easier for those who need it will be a promotion for pg. many commercial db production include such a schedule function, not only for making money,there is user need in practice. Yep, I think it'd be nice. Nobody has volunteered to write such a feature yet, though, and nobody is stepping up to pay someone else to write it. Or at least any efforts so far haven't reached production-quality committable code. The downside of working with an open source database is that there's no incentive to write marketing-checkbox features. Someone has to actually want to put in the time and effort to implement it, usually because they want to use it. yes,it is so complicated for a common user to do such things. ... which is why the VAST majority of people achieve what they need using a separate daemon or just integrate this sort of functionality into their middleware. Neither option is difficult to do. What you want to do - integrate your app directly and completely into the database - is not something that a common user typically wants to do in the first place. It's more common for people who want to hide the database behind a messaging system to instead write a program that accepts messages and embed a database like Berkeley DB, SQLite or Firebird directly into their program, rather than the other way around. PostgreSQL cannot be embedded that way, it's not designed for that kind of use. -- Craig Ringer -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
