f



"Correct" term for a 1:1 relationship between a "database" and an "instance" where > 1 such things are on the same physical server?

What is the "correct" term for a 1:1 relationship between a "database"
and an "instance" where there are at least two such "things" on the
same physical server?

Nearly all the Oracle docs and books define a database something like
the following:

DATABASE - a collection of datafiles and oracle config files; useless
without an "instance" to access the database.

INSTANCE - a collection of background procs and memory structures,
used to access a "database."

Where I work, people typically call each "thing" mentioned in my
Subject: line an "instance" or a "database instance." What is the
"correct" term for having more than one of these "things" on the same,
unpartitioned physical server?

This may be splitting hairs; but when people don't or can't come to
terms, confusion ensues--and that's typically a Bad Thing.

I noticed, or rather a colleague of mine did, that even Tom Kyte mixes
terms. In the book Expert Oracle Database Architecture (2005 edition)
on page 50, in the bullet-pointed definitional paragraph for Instance,
he throws the word "database instance" into the mix. A "no no"
according to my colleague (don't shoot the messenger, please); because
the vernacular seems to be "instance" or "database instance" for the
each "thing."

I like to be precise with terms, but then there are business
stakeholders who use technically imprecise terms; even DBAs seem to
make this mistake.

Would it be less confusing to all concerned simply refer to an "Oracle
SID" to indicate a 1:1 pairing of an "instance" and a "database" where
there are 2 or more of these "things" on a single, unpartitioned
server?

Help! I want to "get it right" without being pedantic and trying to
educate every last stakeholder in a large organization. Maybe
education is the "right" thing to do, but when even DBAs use the term
"instance" incorrectly... well, that might not end well. :-)

Dana

0
7/22/2009 12:24:48 PM
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On Jul 22, 8:24=A0am, dana <dana_at_w...@yahoo.com> wrote:
> What is the "correct" term for a 1:1 relationship between a "database"
> and an "instance" where there are at least two such "things" on the
> same physical server?
>
> Nearly all the Oracle docs and books define a database something like
> the following:
>
> DATABASE - a collection of datafiles and oracle config files; useless
> without an "instance" to access the database.
>
> INSTANCE - a collection of background procs and memory structures,
> used to access a "database."
>
> Where I work, people typically call each "thing" mentioned in my
> Subject: line an "instance" or a "database instance." What is the
> "correct" term for having more than one of these "things" on the same,
> unpartitioned physical server?
>
> This may be splitting hairs; but when people don't or can't come to
> terms, confusion ensues--and that's typically a Bad Thing.
>
> I noticed, or rather a colleague of mine did, that even Tom Kyte mixes
> terms. In the book Expert Oracle Database Architecture (2005 edition)
> on page 50, in the bullet-pointed definitional paragraph for Instance,
> he throws the word "database instance" into the mix. A "no no"
> according to my colleague (don't shoot the messenger, please); because
> the vernacular seems to be "instance" or "database instance" for the
> each "thing."
>
> I like to be precise with terms, but then there are business
> stakeholders who use technically imprecise terms; even DBAs seem to
> make this mistake.
>
> Would it be less confusing to all concerned simply refer to an "Oracle
> SID" to indicate a 1:1 pairing of an "instance" and a "database" where
> there are 2 or more of these "things" on a single, unpartitioned
> server?
>
> Help! I want to "get it right" without being pedantic and trying to
> educate every last stakeholder in a large organization. Maybe
> education is the "right" thing to do, but when even DBAs use the term
> "instance" incorrectly... well, that might not end well. :-)
>
> Dana

In most practical uses you can use the term database to refer to both
the physical database and the instance.  The term instance is short
for database instance which is just a way of specifying the instance
for a specific database when you need to make a distinction

From 11g Glossary

database: Collection of data that is treated as a unit. The purpose of
a database is to store and retrieve related information. Each Oracle
database instance accesses only one database.

instance: A system global area (SGA) and the Oracle Database
background processes constitute an Oracle database instance. Every
time a database is started, a system global area is allocated and
Oracle Database background processes are started. The SGA is
deallocated when the instance shuts down.

Notice the use of the term Oracle database instance appears in both
definitions.

HTH -- Mark D Powell --

0
Mark.Powell (1630)
7/22/2009 1:17:58 PM
Thanks Mark. That was helpful. You wrote:

> In most practical uses you can use the term database to refer to both the physical database and the instance.
....

> database: Collection of data that is treated as a unit. The purpose of
> a database is to store and retrieve related information. Each Oracle
> database instance accesses only one database.

So when people loosely use the term "instance" or "database instance"
they're not completely off base, are they? If each instance can ever
only access one, and only one, database, then it shouldn't be
"considered harmful" to speak this way? Or is the definition implying
that a particular instance can only access one and only one database
at any one time? I think this was what Tom Kyte was saying in the rest
of that book section. I need to re-read it, and will.

Here's another question for you:

1) Would there ever be any practical reason for two instances (procs +
SGA) to access the same database (collection of data treated as a
unit) on the same, unpartitioned physical server?

2) Tangentially related, while I'm at it--is the chief and most
obvious benefit of RAC High Availability? Are claims that RAC can be
used for scalability mostly hype? Last I checked, there was
controversy over this one--guess I need to re-read the "Why You Don't
Need RAC" article; never used RAC and I'm not sure I can even
articulate precisely what it does let alone how it does it. How does
RAC relate to the concepts of "instance" and "database"?

> instance: A system global area (SGA) and the Oracle Database
> background processes constitute an Oracle database instance. Every
> time a database is started, a system global area is allocated and
> Oracle Database background processes are started. The SGA is
> deallocated when the instance shuts down.

> Notice the use of the term Oracle database instance appears in both definitions.

Dana


Dana
0
7/22/2009 1:37:31 PM
On Jul 22, 9:17=A0am, Mark D Powell <Mark.Pow...@eds.com> wrote:
> On Jul 22, 8:24=A0am, dana <dana_at_w...@yahoo.com> wrote:
>
>
>
>
>
> > What is the "correct" term for a 1:1 relationship between a "database"
> > and an "instance" where there are at least two such "things" on the
> > same physical server?
>
> > Nearly all the Oracle docs and books define a database something like
> > the following:
>
> > DATABASE - a collection of datafiles and oracle config files; useless
> > without an "instance" to access the database.
>
> > INSTANCE - a collection of background procs and memory structures,
> > used to access a "database."
>
> > Where I work, people typically call each "thing" mentioned in my
> > Subject: line an "instance" or a "database instance." What is the
> > "correct" term for having more than one of these "things" on the same,
> > unpartitioned physical server?
>
> > This may be splitting hairs; but when people don't or can't come to
> > terms, confusion ensues--and that's typically a Bad Thing.
>
> > I noticed, or rather a colleague of mine did, that even Tom Kyte mixes
> > terms. In the book Expert Oracle Database Architecture (2005 edition)
> > on page 50, in the bullet-pointed definitional paragraph for Instance,
> > he throws the word "database instance" into the mix. A "no no"
> > according to my colleague (don't shoot the messenger, please); because
> > the vernacular seems to be "instance" or "database instance" for the
> > each "thing."
>
> > I like to be precise with terms, but then there are business
> > stakeholders who use technically imprecise terms; even DBAs seem to
> > make this mistake.
>
> > Would it be less confusing to all concerned simply refer to an "Oracle
> > SID" to indicate a 1:1 pairing of an "instance" and a "database" where
> > there are 2 or more of these "things" on a single, unpartitioned
> > server?
>
> > Help! I want to "get it right" without being pedantic and trying to
> > educate every last stakeholder in a large organization. Maybe
> > education is the "right" thing to do, but when even DBAs use the term
> > "instance" incorrectly... well, that might not end well. :-)
>
> > Dana
>
> In most practical uses you can use the term database to refer to both
> the physical database and the instance. =A0The term instance is short
> for database instance which is just a way of specifying the instance
> for a specific database when you need to make a distinction
>
> From 11g Glossary
>
> database: Collection of data that is treated as a unit. The purpose of
> a database is to store and retrieve related information. Each Oracle
> database instance accesses only one database.
>
> instance: A system global area (SGA) and the Oracle Database
> background processes constitute an Oracle database instance. Every
> time a database is started, a system global area is allocated and
> Oracle Database background processes are started. The SGA is
> deallocated when the instance shuts down.
>
> Notice the use of the term Oracle database instance appears in both
> definitions.
>
> HTH -- Mark D Powell --- Hide quoted text -
>
> - Show quoted text -

PS - if you have multiple Oracle database instances running on one
server then there is no specific term for this environment other than
using, "multiple Oracle database instances" or "multiple Oracle
databases" to refer to this setup.  You may also have multiple Oracle
software installations and multiple Oracle Homes.

HTH -- Mark D Powell --



0
Mark.Powell (1630)
7/22/2009 1:41:18 PM
On Jul 22, 8:37=A0am, dana <dana_at_w...@yahoo.com> wrote:
> Here's another question for you:
>
> 1) Would there ever be any practical reason for two instances (procs +
> SGA) to access the same database (collection of data treated as a
> unit) on the same, unpartitioned physical server?
>
>
> Dana
>
> Dana

That, I believe, is the basic definition of RAC -- two or more
instances accessing a single database.


David Fitzjarrell
0
oratune (523)
7/22/2009 2:29:17 PM
On Jul 22, 6:37=A0am, dana <dana_at_w...@yahoo.com> wrote:
> Thanks Mark. That was helpful. You wrote:
>
> > In most practical uses you can use the term database to refer to both t=
he physical database and the instance.
>
> ...
>
> > database: Collection of data that is treated as a unit. The purpose of
> > a database is to store and retrieve related information. Each Oracle
> > database instance accesses only one database.
>
> So when people loosely use the term "instance" or "database instance"
> they're not completely off base, are they? If each instance can ever
> only access one, and only one, database, then it shouldn't be
> "considered harmful" to speak this way? Or is the definition implying
> that a particular instance can only access one and only one database
> at any one time? I think this was what Tom Kyte was saying in the rest
> of that book section. I need to re-read it, and will.
>
> Here's another question for you:
>
> 1) Would there ever be any practical reason for two instances (procs +
> SGA) to access the same database (collection of data treated as a
> unit) on the same, unpartitioned physical server?
>
> 2) Tangentially related, while I'm at it--is the chief and most
> obvious benefit of RAC High Availability? Are claims that RAC can be
> used for scalability mostly hype? Last I checked, there was
> controversy over this one--guess I need to re-read the "Why You Don't
> Need RAC" article; never used RAC and I'm not sure I can even
> articulate precisely what it does let alone how it does it. How does
> RAC relate to the concepts of "instance" and "database"?
>
> > instance: A system global area (SGA) and the Oracle Database
> > background processes constitute an Oracle database instance. Every
> > time a database is started, a system global area is allocated and
> > Oracle Database background processes are started. The SGA is
> > deallocated when the instance shuts down.
> > Notice the use of the term Oracle database instance appears in both def=
initions.
>
> Dana
>

There are also other Oracle things called instances that are not what
we think of as database instances.  For example, an ASM instance is a
bunch of memory structures for controlling storage.  OC4J has
instances.  The Grid API has instances.  I don't even know what
Beehive is, but it has instances.

So all those books are wrong, outside a narrow database-centric view.
Since we are all running this open-source stuff along with the
database now, we, most especially DBA's, need precision in
communication.  Of course, if everyone says something, the language
changes, regardless of whether it is stupid or counterproductive.  The
change itself can be interesting.

jg
--
@home.com is bogus.
The I-Pod of soda machines will dumbfound the person in front of you.
http://www3.signonsandiego.com/stories/2009/jul/22/futuristic-100-flavor-co=
ke-dispenser-tested/?uniontrib

0
joel-garry (4553)
7/22/2009 5:28:28 PM
On Jul 22, 8:24=A0am, dana <dana_at_w...@yahoo.com> wrote:
> What is the "correct" term for a 1:1 relationship between a "database"
> and an "instance" where there are at least two such "things" on the
> same physical server?
>
> Nearly all the Oracle docs and books define a database something like
> the following:
>
> DATABASE - a collection of datafiles and oracle config files; useless
> without an "instance" to access the database.
>
> INSTANCE - a collection of background procs and memory structures,
> used to access a "database."
>
> Where I work, people typically call each "thing" mentioned in my
> Subject: line an "instance" or a "database instance." What is the
> "correct" term for having more than one of these "things" on the same,
> unpartitioned physical server?
>
> This may be splitting hairs; but when people don't or can't come to
> terms, confusion ensues--and that's typically a Bad Thing.
>
> I noticed, or rather a colleague of mine did, that even Tom Kyte mixes
> terms. In the book Expert Oracle Database Architecture (2005 edition)
> on page 50, in the bullet-pointed definitional paragraph for Instance,
> he throws the word "database instance" into the mix. A "no no"
> according to my colleague (don't shoot the messenger, please); because
> the vernacular seems to be "instance" or "database instance" for the
> each "thing."
>
> I like to be precise with terms, but then there are business
> stakeholders who use technically imprecise terms; even DBAs seem to
> make this mistake.
>
> Would it be less confusing to all concerned simply refer to an "Oracle
> SID" to indicate a 1:1 pairing of an "instance" and a "database" where
> there are 2 or more of these "things" on a single, unpartitioned
> server?
>
> Help! I want to "get it right" without being pedantic and trying to
> educate every last stakeholder in a large organization. Maybe
> education is the "right" thing to do, but when even DBAs use the term
> "instance" incorrectly... well, that might not end well. :-)
>
> Dana

You cannot talk about something as complicated as Oracle and get
things right technically without being verbose and wordy and extremely
specific.

Most Oracle DBA ( well many anyhow ) understand the differences
between instances and databases but tend to get sloppy at times when
talking to management, developers, IT operators, etc.

Might be best to count things on a server by server bases ( any VM's
on a server should count as a server )  and define how many instances
each server supports in these categories: single instance oracle
databases and multiple instance oracle databases.  The multiple
instance databases are typically RAC although there is still some OPS
( Oracle Parallel Server ) hanging around still.
0
johnbhurley (2707)
7/22/2009 11:26:25 PM
Thanks Mark, Joel, and John. I hadn't thought about non-database
instances.

> Of course, if everyone says something, the language changes, regardless of whether it is stupid or counterproductive.
>  The change itself can be interesting.

True. I think the Oxford English Dictionary staff changes a word's
definition when a particular threshold of the new definition's
occurence in print and other media has been met.

Dana
0
7/23/2009 5:26:12 PM
On Jul 22, 10:29=A0am, ddf <orat...@msn.com> wrote:
> On Jul 22, 8:37=A0am, dana <dana_at_w...@yahoo.com> wrote:
>
> > Here's another question for you:
>
> > 1) Would there ever be any practical reason for two instances (procs +
> > SGA) to access the same database (collection of data treated as a
> > unit) on the same, unpartitioned physical server?
>
> > Dana
>
> > Dana
>
> That, I believe, is the basic definition of RAC -- two or more
> instances accessing a single database.
>
> David Fitzjarrell

But with RAC you would expect each instance to be running concurrently
on different servers.  While some Oracle 'experts' have managed to
create a RAC setup with multiple instances on a single server the set
up is non-standard, unsupported, and for demonstartion purposes only.

On a UNIX platform it used to be fairly easy to change the instance
idenifier, SID, that was used to identify a running Oracle instance
used to access a database.  That is you could shut the instance down,
make a few quick changes, and start a differently named instance then
access the same database you were just working with from a different
instance name.  Only one instance can access a non-RAC database at a
time.  There was little practical application for this functionality.

HTH -- Mark D Powell --

0
Mark.Powell (1630)
7/24/2009 7:58:49 PM
On Jul 24, 12:58=A0pm, Mark D Powell <Mark.Pow...@eds.com> wrote:
> On Jul 22, 10:29=A0am, ddf <orat...@msn.com> wrote:
>
>
>
> > On Jul 22, 8:37=A0am, dana <dana_at_w...@yahoo.com> wrote:
>
> > > Here's another question for you:
>
> > > 1) Would there ever be any practical reason for two instances (procs =
+
> > > SGA) to access the same database (collection of data treated as a
> > > unit) on the same, unpartitioned physical server?
>
> > > Dana
>
> > > Dana
>
> > That, I believe, is the basic definition of RAC -- two or more
> > instances accessing a single database.
>
> > David Fitzjarrell
>
> But with RAC you would expect each instance to be running concurrently
> on different servers. =A0While some Oracle 'experts' have managed to
> create a RAC setup with multiple instances on a single server the set
> up is non-standard, unsupported, and for demonstartion purposes only.
>
> On a UNIX platform it used to be fairly easy to change the instance
> idenifier, SID, that was used to identify a running Oracle instance
> used to access a database. =A0That is you could shut the instance down,
> make a few quick changes, and start a differently named instance then
> access the same database you were just working with from a different
> instance name. =A0Only one instance can access a non-RAC database at a
> time. =A0There was little practical application for this functionality.
>
> HTH -- Mark D Powell --

Wasn't there something about oltp tuning during the day, then batch/
report at night?  Something is poking at the back of my brain, maybe
it wasn't oracle.

jg
--
@home.com is bogus
http://www.reuters.com/article/rbssTechMediaTelecomNews/idUSN21425536200907=
22
0
joel-garry (4553)
7/24/2009 11:11:04 PM
joel garry schreef:
> On Jul 24, 12:58 pm, Mark D Powell <Mark.Pow...@eds.com> wrote:
>> On Jul 22, 10:29 am, ddf <orat...@msn.com> wrote:
>>
>>
>>
>>> On Jul 22, 8:37 am, dana <dana_at_w...@yahoo.com> wrote:
>>>> Here's another question for you:
>>>> 1) Would there ever be any practical reason for two instances (procs +
>>>> SGA) to access the same database (collection of data treated as a
>>>> unit) on the same, unpartitioned physical server?
>>>> Dana
>>>> Dana
>>> That, I believe, is the basic definition of RAC -- two or more
>>> instances accessing a single database.
>>> David Fitzjarrell
>> But with RAC you would expect each instance to be running concurrently
>> on different servers.  While some Oracle 'experts' have managed to
>> create a RAC setup with multiple instances on a single server the set
>> up is non-standard, unsupported, and for demonstartion purposes only.
>>
>> On a UNIX platform it used to be fairly easy to change the instance
>> idenifier, SID, that was used to identify a running Oracle instance
>> used to access a database.  That is you could shut the instance down,
>> make a few quick changes, and start a differently named instance then
>> access the same database you were just working with from a different
>> instance name.  Only one instance can access a non-RAC database at a
>> time.  There was little practical application for this functionality.
>>
>> HTH -- Mark D Powell --
> 
> Wasn't there something about oltp tuning during the day, then batch/
> report at night?  Something is poking at the back of my brain, maybe
> it wasn't oracle.
> 
> jg
> --
> @home.com is bogus
> http://www.reuters.com/article/rbssTechMediaTelecomNews/idUSN2142553620090722

Taken to the letter, a database on (backup) tape or other media is still 
a database, but not an instance.

Shakespeare

(What's in a name?)
0
whatsin (688)
7/25/2009 11:04:56 AM
Thanks Mark, Joel, and Will. :-)
0
7/27/2009 10:47:16 AM
On Jul 24, 7:11=A0pm, joel garry <joel-ga...@home.com> wrote:
> On Jul 24, 12:58=A0pm, Mark D Powell <Mark.Pow...@eds.com> wrote:
>
>
>
>
>
> > On Jul 22, 10:29=A0am, ddf <orat...@msn.com> wrote:
>
> > > On Jul 22, 8:37=A0am, dana <dana_at_w...@yahoo.com> wrote:
>
> > > > Here's another question for you:
>
> > > > 1) Would there ever be any practical reason for two instances (proc=
s +
> > > > SGA) to access the same database (collection of data treated as a
> > > > unit) on the same, unpartitioned physical server?
>
> > > > Dana
>
> > > > Dana
>
> > > That, I believe, is the basic definition of RAC -- two or more
> > > instances accessing a single database.
>
> > > David Fitzjarrell
>
> > But with RAC you would expect each instance to be running concurrently
> > on different servers. =A0While some Oracle 'experts' have managed to
> > create a RAC setup with multiple instances on a single server the set
> > up is non-standard, unsupported, and for demonstartion purposes only.
>
> > On a UNIX platform it used to be fairly easy to change the instance
> > idenifier, SID, that was used to identify a running Oracle instance
> > used to access a database. =A0That is you could shut the instance down,
> > make a few quick changes, and start a differently named instance then
> > access the same database you were just working with from a different
> > instance name. =A0Only one instance can access a non-RAC database at a
> > time. =A0There was little practical application for this functionality.
>
> > HTH -- Mark D Powell --
>
> Wasn't there something about oltp tuning during the day, then batch/
> report at night? =A0Something is poking at the back of my brain, maybe
> it wasn't oracle.
>
> jg
> --
> @home.com is bogushttp://www.reuters.com/article/rbssTechMediaTelecomNews=
/idUSN21425536...- Hide quoted text -
>
> - Show quoted text -

Yes.  You would use a separate pfile then just referred to an init.ora
so you would want to use a separate instance identifier, SID, at the
OS level so that Oracle would select the right init.ora
automatically.  The alternate was to use the same SID but specify the
init.ora via the startup command.

--  Mark D Powell --
0
Mark.Powell (1630)
7/28/2009 1:55:51 PM
Reply:

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Hi, I'm just getting to discover ruby, but I find it very nice programming language. I just still don't understand how the "or" and "and" in ruby... I was playing with ruby and for example made a def to print Stem and Leaf plot (for those who didn't have a statistics course or slept on it, e.g. http://cnx.org/content/m10157/latest/) Here is the Beta version of it: class Array def n ; self.size ; end def stem_and_leaf(st = 1) # if st != (2 or 5 or 10) then ; st = 1 ; end k = Hash.new(0) self.each {|x| k[x.to_f] += 1 } k = k.sort{|a, b| a[0].to_f <=&g...

why "::", not "."
Why does the method of modules use a dot, and the constants a double colon? e.g. Math::PI and Math.cos -- Posted via http://www.ruby-forum.com/. On Oct 26, 2010, at 01:48 , Oleg Igor wrote: > Why does the method of modules use a dot, and the constants a double > colon? > e.g. > Math::PI and Math.cos For the same reason why inner-classes/modules use double colon, because = they're constants and that's how you look up via constant namespace. Math::PI and ActiveRecord::Base are the same type of lookup... it is = just that Base is a module and PI is a float....

"my" and "our"
Hi, while testing a program, I erroneously declared the same variable twice within a block, the first time with "my", the second time with "our": { my $fz = 'VTX_Link'; .... ( around 200 lines of code, all in the same block) our $fz = 'VTX_Linkset'; ... } So the initial contents of the $fz declared with "my" is lost, because "our" creates a lexical alias for the global $fz, thus overwriting the previous "my" declaration. It was my error, no question. But I wonder why Perl doesn't mention this - even with "use s...

"out" and "in out"
Hi i found the following explaination: In Ada, "in" parameters are similar to C++ const parameters. They are effectively read-only within the scope of the called subprogram. Ada "in out" parameters have a reliable initial value (that passed in from the calling subprogram) and may be modified within the scope of the called procedure. Ada "out" parameters have no reliable initial value, but are expected to be assigned a value within the called procedure. What does "have no reliable initial value" mean when considering the "out" parameter? By c...

about "++" and "--"
why this program snippet display "8,7,7,8,-7,-8" the program is: main() { int i=8; printf("%d\n%d\n%d\n%d\n%d\n%d\n",++i,--i,i++,i--,-i++,-i--); } > why this program snippet display "8,7,7,8,-7,-8" Ask your compiler-vendor because this result is IMHO implementation-defined. Check this out: http://www.parashift.com/c++-faq-lite/misc-technical-issues.html#faq-39.15 http://www.parashift.com/c++-faq-lite/misc-technical-issues.html#faq-39.16 Regards, Irina Marudina fxc123@gmail.com wrote: > why this program snippet display "8,7,7,8,-7,-8&q...

"If then; if then;" and "If then; if;"
I have a raw data set which is a hierarchical file: H 321 s. main st P Mary E 21 F P william m 23 M P Susan K 3 F H 324 S. Main St I use the folowing code to read the data to creat one observation per detail(P) record including hearder record(H): data test; infile 'C:\Documents and Settings\retain.txt'; retain Address; input type $1. @; if type='H' then input @3 Address $12.; if type='P' then input @3 Name $10. @13 Age 3. @16 Gender $1.; run; but the output is not what I want: 1 321 s. main H 2 321 s. main P Mary E 21 F 3 321 s...

Function ( "TxtA TxtA TxtA TxtB TxtC TxtA"; "TxtC" ; 1 ; "TxtA" ; 1 ) -> "TxtB" ?
Hi How would you to extract a string between "TxtC" an "TxtA" ("TxtB") with a function like this one : Function ( "TxtA TxtA TxtA TxtB TxtC TxtA"; "TxtC" ; 1 ; "TxtA" ; 1 ) -> "TxtB" ? On Dec 4, 7:51=A0am, "Grolo" <Gr...@yahoono1phub.com> wrote: > Hi > > How would you to extract a string between "TxtC" an "TxtA" ("TxtB") with = a > function like this one : > > Function ( "TxtA TxtA TxtA TxtB TxtC TxtA"; "TxtC" ; 1 ; "TxtA"...

"In" "Out" and "Trash"
I just bought a new computer and I re-installed Eudora Light on my new computer. But when I open Eudora, the "In", "Out" and "Trash" links are not on the left side of the screen the way they were on my old computer. How can I get these links back on the left side of the screen? Thank you. On 25 Mar 2007 09:49:22 -0700, "abx" <abfunex@yahoo.com> wrote: >I just bought a new computer and I re-installed Eudora Light on my new >computer. But when I open Eudora, the "In", "Out" and "Trash" links >are ...

Does it need a ";" at the very after of "if" and "for"
write code like: int main(void) { int a=10; if(a<20) {} } Compiler ok on dev-cpp . don't we have to add a ";" after if statement? marsarden said: > write code like: > > int main(void) > { > int a=10; > if(a<20) > {} > } > > Compiler ok on dev-cpp . don't we have to add a ";" after if > statement? The syntax for 'if' is: if(expression) statement There is no semicolon after the ) but before the statement. The statement is either a normal statement (which can be empty), ending in a semicolon:- if(expr) ...

(mapcar 'quote '("1" "2" "3" "4"))
(mapcar 'quote '("1" "2" "3" "4")) returns ((quote "4") (quote "4") (quote "4") (quote "4")) Interesting and (for me) unexpected. Because (mapcar 'read '("1" "2" "3" "4")) returns (1 2 3 4) and (mapcar 'princ '("1" "2" "3" "4")) gives 1234("1" "2" "3" "4") Why isn't (mapcar 'quote '("1" "2" "3" "4")) returning ((quote "1") (quote "2") (quote "3") (quote "4")) Tom Haws www.hawsedc.com Probably has to do with the fact that 'arg and (quote arg) are equivalent, and LISP gets confused by the construct 'quote, which is about the same as (quote (quote arg)). But I don't pretend to know all of the mechanics of the error; the results are somewhat different in R14, BTW: Command: (mapcar 'quote '("1" "2" "3" "4")) ((<Subr: #22e3e40> "4") (<Subr: #22e3e40> "4") (<Subr: #22e3e40> "4") (<Subr: #22e3e40> "4")) ___ "Tom Haws" <hawstom@despammed.com> wrote in message news:77317472.0309160733.45ea9d8c@posting.google.com... > (mapcar 'quote '("1" "2" "3"...

elementvise division "1./a" versus "1 ./ a"
Hi, I wonder why there is a difference in the way scilab interprets "1./a" and "1 ./ a". Is this intentionally or is it a bug? -->a=[2 3 4] a = ! 2. 3. 4. ! -->1./a ans = ! 0.0689655 ! ! 0.1034483 ! ! 0.1379310 ! -->1 ./ a ans = ! 0.5 0.3333333 0.25 ! --> -Torbj�rn. Torbj�rn Pettersen wrote: > Hi, > I wonder why there is a difference in the way scilab interprets "1./a" > and "1 ./ a". Is this intentionally or is it a bug? > > -->a=[2 3 4] > a = > > ! 2. 3. 4. ! > > -->1./a > ans = > > ! 0.0689655 ! > ! 0.1034483 ! > ! 0.1379310 ! > > -->1 ./ a > ans = > > ! 0.5 0.3333333 0.25 ! > It's feature plus an unlucky situation. 1./a is intepreted as (1.0)/a which by definition computes the pseudo-inverse of a . Contrary to that 1 ./ a is the (./) operator. It's expanded into ones(a) ./ a which gives elementwise devision. So it's just that 1. is a floating point constant. There is no problem with say a./b ! Helmut Jarausch Lehrstuhl fuer Numerische Mathematik RWTH - Aachen University D 52056 Aachen, Germany Hm yes you are right... but I'm not sure I like that feature - It took to long to figure out where the error was :-) -Torbj�rn. Helmut Jarausch wrote: > Torbj�rn Pettersen wr...

Changing "Figure 1" to "Scheme 1"
Hi I'm trying to complete a 1-page abstract and am using floatflt to wrap the figures. I have tried to find the answers to the following, but time is of the essence at the moment. My question is regarding one of the captions: I want "Scheme 1" to replace "Figure 2" in the 2nd image I have included. Advice on this is much appreciated and also how to remove the colon after "Figure X:"/"Scheme X:". This is what is written: \usepackage[rflt]{floatflt} \setlength\figgutter{25pt} \newcommand{\incffig}[1]{\includegraphics[width=\floatfltwidth]{#1}} \begin{document} some text \begin{floatingfigure}[l]{0.55\linewidth} \incffig{thefigure} \def\fnum@figure{thecaption} \end{floatingfigure} some more text Hi, I used the caption2 with luck to change the figure captions in an earlier project, but caption2 seems to be obsolete and superseeded by the caption package. In any case, maybe one of them may do the trick for you. Best, Jon Nat wrote: > Hi > > I'm trying to complete a 1-page abstract and am using floatflt to wrap > the figures. I have tried to find the answers to the following, but > time is of the essence at the moment. My question is regarding one of > the captions: I want "Scheme 1" to replace "Figure 2" in the 2nd image > I have included. Advice on this is much appreciated and also how to > remove the colon after "Figure X:"/"Scheme X:". > > This...

why have both "." and "->" ?
I used to remember why c++ needed both ? Could somebody help me here ? For example class A{ f(); }; A* aa; You could do either "aa->f()" or "(*aa).f()". So why does C++ need both operators. Raj "raj" <rajkumar@hotmail.com> schreef in bericht news:d7fee6d0.0406230748.694b966b@posting.google.com... > I used to remember why c++ needed both ? > Could somebody help me here ? > > For example > > class A{ > f(); > }; > > A* aa; > > You could do either "aa->f()" or "(*aa).f()". So why does C++...

"bb = bb + 1" vs "bb += 1"
Hi ! The following code does not compile (as expected): class SimpleJava { public static void main(String args[]) { System.out.println("SimpleJava ...."); byte bb = 0; bb = bb + 1; System.out.println("bb = " + bb); } } While the following one is compiling: class SimpleJava { public static void main(String args[]) { System.out.println("SimpleJava ...."); byte bb = 0; bb += 1; System.out.println("bb = " + bb); } } The += operator is specific to each primitive, so it "know" how to work with integers. The ope...

How to alias "n1" to "n 1" and "n2" to "n 2" and so on (with style)
I have the following bash function: function ..() { counter=0 case "$1" in [0-9][0-9] ) while [ $counter -lt $1 ] do cd .. counter=$(($counter+1)) done ;; * ) echo "staying where I am, give me a number (<99) next time :)" ;; esac } The allows me to move up, say 4 levels, using ".. 4" Now, typing the space annoys me so I define the following aliases: alias ..='.. 1' alias ..2='.. 2' alias ..3='.. 3' alias ..4='.. 4' alias ..5='.. 5' Not very elegant I con...

"order by" And "limit = 1"
Folks, I want to SELECT the single highest value of x. What does "Order by" really order, the full set of table rows before the single selection is returned, or only the returned row? (which wd clearly be useless in this case.) Or is there better SQL? Thanks. AS ashore wrote: > Folks, I want to SELECT the single highest value of x. What does > "Order by" really order, the full set of table rows before the single > selection is returned, or only the returned row? (which wd clearly be > useless in this case.) > > Or is there better SQL? Thanks. > ...

fnmatch("\\\\", "\", 0) == 1 ???
FYI fnmatch("\\\\", "\", 0) in DJGPP returns 1(no match) -- the escaping functionality seems to be broken. The same function call returns 0 (match) in Linux (Red Hat 9 kernel 2.4.20) -- what it should be. Alex Alexei A. Frounze wrote: > FYI fnmatch("\\\\", "\", 0) in DJGPP returns 1(no match) -- the obvious correction (missed one slash): fnmatch("\\\\", "\\", 0) > escaping functionality seems to be broken. > The same function call returns 0 (match) in Linux (Red Hat 9 kernel > 2.4.20) -- what it should be. Alex ...

Urgent JAVA Requirement in """"""NEW YORK"""""""""
Hello Partners, How are you ? Please find the requirement below. Location : NY Duration : 8 mnths Rate :Open Job description: Java/J2EE Web Service Developer =B7 (4+ years of application development experience in Java/J2EE and Web service technologies. =B7 Experience with spring & Hibernate. =B7 Experience with J2EE Application Server (preferably Web logic). =B7 Preferable Aqua logic DSP Experience =B7 Preferable Sonic ESB Composite Service experience Experience w...

"use constant X=>(1,2);" or "use constant X=>[1,2];"?
What's better? use constant X=>(1,2); or use constant X=>[1,2]; On Sat, 8 Dec 2007 09:44:59 -0800 (PST), Victor Porton <porton@narod.ru> wrote: >What's better? > > use constant X=>(1,2); > >or > > use constant X=>[1,2]; What's better? my @x = (1,2); or my $x = [1,2]; Michele -- {$_=pack'B8'x25,unpack'A8'x32,$a^=sub{pop^pop}->(map substr (($a||=join'',map--$|x$_,(unpack'w',unpack'u','G^<R<Y]*YB=' ..'KYU;*EVH[.FHF2W+#"\Z*5TI/ER<Z`S(G.DZZ9OX0Z')=~/./g)x...

Web resources about - "Correct" term for a 1:1 relationship between a "database" and an "instance" where > 1 such things are on the same physical server? - comp.databases.oracle.server

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