Hi,
I am getting some strange exceptions using MonetDB JDBC 1.8/1.9, and I
decided to look into the code. While inspecting the code I came across
these strange lines in MonetConnection.executeQuery(String[] templ,
String query) method
(http://dev.monetdb.org/hg/MonetDB/file/718da8ca0a1a/java/src/nl/cwi/monetdb…).
In my case, these lines are executed for sure when doing a batch
insert. So, suppose that the batch contains the following commands (as
constructed by the MonetStatement.executeBatch() method):
exec 1(1, 957339737330229055);
exec 1(2, 278262503670654331);
exec 1(805306369, 3763943296910752235)
The lines in question take the above commands as a string, prepend a
's' character and append a ';' at the end. The resulting commands,
which are written in the server's socket, are the following:
sexec 1(1, 957339737330229055);
exec 1(2, 278262503670654331);
exec 1(805306369, 3763943296910752235);
First of all, I am not familiar with the internals of JDBC drivers.
Taking this into account, is this what it should be? From a symmetric
point of view, I would assume that the correct would be the following:
sexec 1(1, 957339737330229055);
sexec 1(2, 278262503670654331);
sexec 1(805306369, 3763943296910752235);
That is, it should prepend a 's' character before an exec command.
Last, are these exec commands (with or without a prepending 's')
specific to MonetDB? In either case, is there any documentation to get
familiar with their meaning?
Thanks a lot,
Babis
The MonetDB team at CWI/MonetDB BV is pleased to announce the
Apr2011-SP1 bugfix release of the MonetDB suite of programs.
At the time of this release, we also officially changed to our new
website at http://www.monetdb.org/. This new website is our central
source of information, and comes with our new logo and style.
For details on this release, please see the release notes at
<http://www.monetdb.org/Downloads/ReleaseNotes>.
Hi,
is there a "CREATE COLUMN TABLE xyz" like statement in MonetDB or will every
"CREATE TABLE" create a column table? Can I create "normal" row store tables
in MonetDB at all?
I have read http://monetdb.cwi.nl/SQL/Documentation/Table-Definition.htmlbut
did not found the information I was looking for.
Kind regards.
michael
Hi,
I am trying to get started with MonetDB in order
to assess its response time for an in-house dataset.
I managed to configure/make/install it on my
MacBook Pro (I have joined the custom Portfile
I used for this purpose at the end of this email in
case it matters).
Nevertheless, when I go through the "Getting started"
instructions, mclient is asking for credentials that I
never had a chance to explicitly set:
ph7:~$ monetdbd start
ph7:~$ monetdbd get all
property value
hostname Solaris.local
dbfarm /opt/local/var/monetdb5/dbfarm
mserver /opt/local/bin/mserver5
logfile merovingian.log
pidfile merovingian.pid
sockdir /tmp
port 50000
controlport 50001
discoveryport 50000
exittimeout 60
forward proxy
discoveryttl 600
passphrase <unknown>
mapisock /tmp/.s.monetdb.50000
controlsock /tmp/.s.merovingian.50001
ph7:~$ monetdb create demo
created database in maintenance mode: demo
ph7:~$ monetdb status
name state uptime health last crash
demo locked
ph7:~$ monetdb release demo
taken database out of maintenance mode: demo
ph7:~$ monetdb status
name state uptime health last crash
demo stopped
ph7:~$ mclient -d demo
user(ph7):
password:
InvalidCredentialsException:checkCredentials:invalid credentials for user 'ph7'
Which credentials am supposed to use to launch
mclient? I am willing to try any workaround as, at
this point, I am not concerned with security at all.
Thanks in advance,
- Philippe
---------------------------------------------------------
# ph7's custom Portfile
# $Id
PortSystem 1.0
name MonetDB
version 11.3.1
categories databases
platforms darwin
maintainers nomaintainer
description MonetDB is an open-source database system for
high-performance applications in data mining, OLAP, GIS, XML Query,
text and multimedia retrieval. MonetDB often achieves a significant
speed improvement for SQL and XQuery over other open-source systems.
homepage http://www.monetdb.org
master_sites http://dev.monetdb.org/downloads/sources/Latest/
distfiles MonetDB-${version}.tar.bz2
use_bzip2 yes
checksums md5 f48869c87a56604d1c06f7d8243554f9 \
sha1 03a29a5e00a90d5294443ffb849167a2c108302e \
rmd160 c9bcdff333a60aad42dc8504c458335494e749f1
configure.args --enable-debug=no --enable-assert=no --enable-optimize=yes
Hi,
I am trying to use monetDB in embedded mode. The sample at
"http://monetdb.cwi.nl/SQL/Documentation/A-Simple-Example.html#A-Simple-Exam…"
suggests that we can interface to the data base using "embedded_sql()"
method in combination with "embeddedclient.h". I dont seem to find this
method in the library "libmapi.so.3"; neither the include file in the code
base. Is "embedded mode" still supported? is there an alternate way of
connecting to embedded monetDB server?
PS: I am using monedDB5 - April 2011 release.
Thanks,
Ram
--
View this message in context: http://old.nabble.com/using-MonetDB-in-embedded-mode---mapi-interface-tp316…
Sent from the monetdb-users mailing list archive at Nabble.com.
Hi,
I am designing the schema of our brand new MonetDB database,
and I am not sure whether my previous data modeling instincts are
still relevant ;-). In particular, I am wondering:
A) Does the definition of primary keys / foreign keys improve
MonetDB performance?
B) I need to do joins with a table whose natural key which is the
combination of (bigint, varchar(51)). Is it best to:
1) just add these 2 columns to the dependent tables, and join
on these 2 columns.
2) create a single varchar column that would be the concatenation
of the bigint + varchar(51) and join on this single varchar column
3) Introduce a numeric+sequential surrogate key (presumably
generated from a sequence), and join on the surrogate key.
I am especially interested in the performance / acidental complexity tradeoffs
in this situation.
Thanks in advance,
- Philippe
Hi,
I am trying to operationalize our MonetDB usage and need some
advice. What is the best way to do upserts in MonetDB?
(https://secure.wikimedia.org/wikipedia/en/wiki/Upsert)
Our application stores its data in a reference database (not MonetDB)
and need to export some of its (derived) data in MonetDB for
our real-time analytics needs. This "population" of
MonetDB can happen in a couple of ways:
A) In "real-time", on a "one row at a time" basis, when the
application detects that it would be valuable to update
the analytics information.
B) Nightly in a batch oriented basis, to make sure that no
information was lost due to a glitch/downtime during the day.
C) We also periodically "refresh" all historical data in a batch
oriented mode when we find bugs in the way we are deriving
the data or what to derive new analytics from the same
reference data.
And whatever triggered the update, the rule is that the last
update "wins" (and contains the full data).
I am explaining this to illustrate why upserts would be very
convenient. They would allow me to use the same code in
all situations (A, B, C) and in "row" mode as well as in
"batch" mode.
If, as I suspect there is no out-of-the-box support for upserts,
what is the best way to achieve them efficiently in batch mode.
I am open to any (performant) solution, it does not have to be
SQL based.
Thanks in advance,
- Philippe
PS: Thanks a lot for MonetDB, I am completely amazed by
its performance for our analytics queries.
It seems that in OpenBSD sys/sysctl.h requires sys/param.h
(http://lists.gnu.org/archive/html/bug-autoconf/2005-08/msg00015.html).
I've found this workaround, but I won't test it until tomorrow
probably: http://lists.gnu.org/archive/html/bug-autoconf/2005-08/msg00015.html
I also don't know exactly how to apply the above workaround (or any
other) in the MonetDB Makefile(s ?).
On Wed, May 4, 2011 at 6:27 PM, Michael Sioutis <sioutis(a)di.uoa.gr> wrote:
> It seems that in OpenBSD sys/sysctl.h requires sys/param.h
> (http://lists.gnu.org/archive/html/bug-autoconf/2005-08/msg00015.html).
> I've found this workaround, but I won't test it until tomorrow
> probably: http://lists.gnu.org/archive/html/bug-autoconf/2005-08/msg00015.html
>
> I also don't know exactly how to apply the above workaround (or any
> other) in the MonetDB Makefile(s ?).
>
> On Wed, May 4, 2011 at 6:20 PM, Michael Sioutis <papito.dit(a)gmail.com> wrote:
>> I can't find any of HAVE_SYS_SYSCTL_H and KERN_PROC_PATHNAME defined
>> in my config.log.
>> Also, I have a warning about sysctl.h, which is in the
>> configuration.log I posted earlier (my first post).
>>
>> The important part is this:
>> configure: WARNING: sys/sysctl.h: present but cannot be compiled
>> configure: WARNING: sys/sysctl.h: check for missing prerequisite headers?
>> configure: WARNING: sys/sysctl.h: see the Autoconf documentation
>> configure: WARNING: sys/sysctl.h: section "Present But Cannot Be Compiled"
>> configure: WARNING: sys/sysctl.h: proceeding with the compiler's result
>> configure: WARNING: ## ------------------------------- ##
>> configure: WARNING: ## Report this to info(a)monetdb.org ##
>> configure: WARNING: ## ------------------------------- ##
>>
>> On Wed, May 4, 2011 at 6:06 PM, Fabian Groffen <Fabian.Groffen(a)cwi.nl> wrote:
>>> Thanks for the summarisation!
>>>
>>> On 04-05-2011 17:56:54 +0300, Michael Sioutis wrote:
>>>> To sum it up..
>>>>
>>>> add
>>>> #include <pthread.h>
>>>> #include <pthread_np.h>
>>>
>>> hmm, do you really need pthread_np.h? That seems like a non-standard
>>> header to me.
>>>
>>>> and...
>>>> 2011-05-04 17:44:29 MSG mydb[19795]: !MALException:malInclude:could
>>>> not open file: mal_init
>>>
>>> This indicates some bigger problem...
>>>
>>>> 2011-05-04 17:44:29 MSG mydb[19795]: #warning: unable to determine binary location, please use --set monet_mod_path=/path/to/... to allow finding modules
>>>
>>> ... and this causes it.
>>>
>>> Can you tell me if HAVE_SYS_SYSCTL_H and KERN_PROC_PATHNAME are defined
>>> for you?
>>> common/utils/mutils.c is apparently unable to find the executable path
>>> on OpenBSD.
>>> Perhaps KERN_PROC_PATHNAME is not in sys/sysctl.h on OpenBSD?
>>>
>>> ------------------------------------------------------------------------------
>>> WhatsUp Gold - Download Free Network Management Software
>>> The most intuitive, comprehensive, and cost-effective network
>>> management toolset available today. Delivers lowest initial
>>> acquisition cost and overall TCO of any competing solution.
>>> http://p.sf.net/sfu/whatsupgold-sd
>>> _______________________________________________
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>>> MonetDB-users(a)lists.sourceforge.net
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>>>
>>
>