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grant tailor

8:16 AM

sorry to border anyone no one seems to help here dba.stackexchange.com/questions/8756/…

need help please dba.stackexchange.com/questions/8756/…

Jack Douglas

9:02 AM

Hi @grant and welcome to the site and our lovely chat room

It is quite likely that someone will have a look at your question in the next 12 hours or so - most of the MySQL experts are probably asleep right now :)

also things are a lot quieter over the weekend and will start picking up soon - you only posted it 4 hours ago are you in a rush?

@MarkStoreySmith Do you live in London?

Mark Storey-Smith

@JackDouglas Yup, Clapham.

Jack Douglas

9:33 AM

@MarkStoreySmith I can probably make the 8th. btw I work in Barnes a couple of days a week - small world...

ConcernedOfTunbridgeWells

10:39 AM

@MarkStoreySmith Liverpool St. is pretty handy for me. The trains from Brentwood go into LS.

gbn

Morning all

Jack Douglas

10:56 AM

@gbn morning, it's freezing here you'll be amused to know :-)

gbn

@JackDouglas I'm in Switzerland this week so found it a tad baltic today

bloody glorious when I left Malta on Saturday

Jack Douglas

you on holiday or moonlighting with your ex employer?

gbn

Just banal admin

The continent is big on registering, deregistering, permits, big brother etc

and I have to wrap things up here

Jack Douglas

I see - what a pain in the neck. You have your compensation though so I wont feel too sorry for you :)

2

Q: Who's up for a RAID10 challenge?

What's better for performance with, say, 16 drives? some say RAID10 the lot others suggest have a smaller array dedicated to logs and RAID10 the rest I'm wondering if this is an opportunity for a project to raise the profile of the site - IIRC I've got 16+ 72GB 15K U320 drives and the other t...

have you got an opinion on this btw?

gbn

11:21 AM

Like @Mark I'd like to know Brent's thinking because it's counter intuitive

6-8 disks, yes, RAID 10

but 16?

Why no advantage to separate logs and some of tempdb?

mrdenny says R1, separate volumes: dba.stackexchange.com/a/8582/630

...but a single R1 for data may be too small

Brent and he know each other, no?

Jack Douglas

@gbn not sure tbh

had a long conversation with @ConcernedOfTunbridgeWells yesterday and I think the advantage of separating is probably more down to stripe size than anything else but there are lots of things we'd like to test

partly a bit of fun, and partly a subject to blog

gbn

yep

most DBs won't notice it.

Jack Douglas

he has a serious amount of kit in his graveyard - including about 50 FC disks :)

gbn

many years ago I benchmarked RAID for my boss

Jack Douglas

@gbn well those just need to ahve one RAID10 because it is simpler

gbn

11:29 AM

yep

Jack Douglas

there are a lot of variables

but I'm keen to get a better understanding of the nuances in the process

gbn

Everyone's experience is different

Jack Douglas

eg diminishing returns, hw/sw, different controllers, channel configs etc

in other words if you are looking for a one-size-fits-all you are out of luck so hard cheese do the testing on your own kit :)

probably a good answer to most of the Qs about it

gbn

if someone ask and they have 16 disks and/or SAN then we can say that

but the few we've seen and 6-8 disks. Not really many options

one size fits all is the answers

Jack Douglas

6-8 disks is "what I can fit in my server" - I expect we'll get some Qs in the 14-disks territory of 1 external DAS array before the jump to SAN.

ConcernedOfTunbridgeWells

11:41 AM

@JackDouglas Another advantage is that quiet log disks will work better on a large volume of small sequential writes, which is what happens on DB log files. How much the random writes affect log activity on a 16-disk array is a good question.

Jack Douglas

@ConcernedOfTunbridgeWells exactly - there is a trade off because of course a 16 disk array has a lot more overall bandwidth - and you are also eating into that when you separate off 4 to dedicate to logs. I'd like to quantify this at least to some degree

and it will depend on how the RDBMS schedules writes

so might vary by RDBMS

gbn

11:56 AM

at my last shop we also used tempdb heavily

so we have high TPS, lots of tempdb activity

if your testing could add a tempdb load too

Jack Douglas

@gbn fancy helping us put some test scenarios together? :)

gbn

could do. Will have a think about some OLTP patterns. Might be able to blag some .net test harnesses that generated loads at my last shops

Jack Douglas

sounds good - we'll log our progress with the hardware on that meta Q

would be helpful to have some votes on it if we want support from SE

if you haven't already :)

ConcernedOfTunbridgeWells

12:22 PM

According to the docs the ASR-2200s and Smartarray 6404 both support packetised SCSI, which means the handshaking overhead will be negligible on a homogeneous array. A U320 channel could then be assumed to behave much like a 3Gb SAS channel from that respect.

i.e. Disk performance data from a SCSI subsystem should be reasonably applicable to the same config of SAS disks with the same number of channels up to any controller performance limits - without too much hand waving.

And an ebay search shows you can get used ones fairly cheaply in London if you want more - even ones with disks.

And Smartarray 6404s and ASR-2200s controllers are quite cheap on Ebay.

Jack Douglas

1:01 PM

@ConcernedOfTunbridgeWells I have a couple of older LSI U320 cards: amazon.com/LSI-Logic-MEGARAID-320-2-64MB-3202064/dp/B00008PGJN

never quite trusted Adaptec

who makes the HP cards? HP themselves or are they rebadged?

gbn

1:19 PM

eingestellt

oops

The Scunthorpe problem again...

bbc.co.uk/news/world-europe-16002460

JNK

it's different though

since the entire string of the place name is the issue

not a substring

not the same as clbuttic

gbn

scunthorpe includes whole names

Fucking, Austria

{{Infobox Settlement |name = Fucking |official_name = |other_name = |native_name = |native_name_lang = |nickname = |settlement_type =Village |total_type = |motto = |image_skyline = Fucking, Austria, street sign cropped.jpg |imagesize = |image_caption = The frequently stolen traffic sign, at the entrance to the village of Fucking. |image_flag = |flag_size = |image_seal = |seal_size = |image...

No ambiguity there

JNK

1:35 PM

The Heap (NSFW)

ConcernedOfTunbridgeWells

@JackDouglas I think the Smartarray cards are made in-house, probably descended from the Compaq side.

@JackDouglas I've found the ASR-2200s cards to be quite good. The BIOS and array functionality on the cards is pretty strong, and the cards seem to be pretty quick.

@gbn At one point I used to live just up from a place called Pratt's Bottom

@JackDouglas I also have a LSI 320-4X, but I never ran it up for test.

Jack Douglas

LSI OEM for a lot of other I think (definately Dell)

in my experience that are solid rather than super-fast

ConcernedOfTunbridgeWells

@JackDouglas A lot of IBM serverraid and Dell PERC cards are rebadged LSI or adaptec units.

Jack Douglas

but I haven't had one in 4 or 5 years

ConcernedOfTunbridgeWells

There is a faster version of the 320-2, it's called the 320-2X, and you could still buy them new not that long ago IIRC. However, I've never actually used one.

Jack Douglas

1:43 PM

thats the PCI-X version I think

might be the ones I've got, come to think of it - will have to check

DTest

2:19 PM

helloo!

gbn

Hello

DTest

you get a new job @gbn? been awol for the last week or so dealing with work stuff :(

gbn

nah, same gig for last months.The one where I'm learning to love MySQL...

DTest

2:37 PM

ah, misunderstood the transcripts then! MySQL rocks or something

JNK

"insert overhead for indexes is negligible"?

1

A: Performance overhead of single column vs multiple column indexes

The INSERT overhead of INDEXes is normally negligible regardless of single or multi column. Unless writes significantly out weigh reads, always include whatever indexes are necessary to improve the performance of your queries. In some case multiple single column indexes sufficiently boost the p...

adopilot

good afternoon

JNK

hi

adopilot

Can I ask for one fast help

This is perhapes too easy to make new question on main site

JNK

you can always ask

whether or not you get an answer...different issue :)

adopilot

2:46 PM

how to make this query work

select * from dbo.table inner join dbo.function(dbo.table.someclun) as a on tble.id=a.id

how I can pass valu of some clunm to table valued funncion

inside join clue

Mark Storey-Smith

But you really really shouldn't

JNK

open a question for that you

that one

you need to use cross apply and it's beyond the scope of chat

adopilot

All righ I'll open a question

but this is lakie bad spot on my profile

when I asking stupid questions

ConcernedOfTunbridgeWells

@adopilot Just look up cross apply in the docs and follow your nose then.

Mark Storey-Smith

No such thing as a stupid question. There are stupid answers but no stupid questions

adopilot

2:50 PM

@ConcernedOfTunbridgeWells Thanx I did it , Cross appy does the work

Mark Storey-Smith

So chaps, are we considering beer Thursday?

jcolebrand

oy, I'm considering morphine monday

JNK

is this in the UK mark?

Mark Storey-Smith

@JNK Yup. There's a UK SQL Server user group drinks in London Thursday. A few of use were thinking about tagging on a dba.se crowd

DTest

ugh and I thought today I'd have some downtime :(

@MarkStoreySmith considering some beer right now

JNK

2:54 PM

I'm in new england

unfortunately

Mark Storey-Smith

@DTest Had a 2 pint lunch, so less productive this afternoon!

DTest

@JNK it's ok... new is always better

@markstoreysmith hah...thinking about it instead of my morning coffee

ConcernedOfTunbridgeWells

@JNK Well, you could just hop on Concorde and .. oh, wait :(

JNK

once they finish the AtlanticOceaunnel I can just take a lorry across

ConcernedOfTunbridgeWells

@JNK That's a very British Idiom. Sure you're not a pom?

JNK

3:20 PM

@ConcernedOfTunbridgeWells don't know pom, I know a few choice idiomatic expressions

ConcernedOfTunbridgeWells

@JNK Antipodean slang (Aus/NZ) for British people. Aprocryphally it's short for 'Prisoner of Mother England', referring to convicts transported to Australia in the 19th century, but I'm not sure if that's the real etymology.

JNK

3:42 PM

sounds like a backronym to me

ConcernedOfTunbridgeWells

Maybe. It's been around since at least the first half of the 20th century. Snopes.com has an article.

snopes.com/language/acronyms/pommy.asp

JNK

4:33 PM

anyone know about AS400 databases?

0

Q: Simple select statement when member is involved

I am sure this is as simple as a question can get but I have been stumped on it so figured that I would ask in hope of a quick response. Using an OLEDB connection I want to do a select statement but for the table I am selecting from, a table member also has to be there too which seems to be mess...

sql vb.net vba ibm-midrange

jcolebrand

I thought they were COBOL driven

ConcernedOfTunbridgeWells

@jcolebrand The O/S has native ISAM/VSAM file support and DB2/400 sits on top of that.

You can access the files through DB2/400 or directly as files, I believe.

jcolebrand

so really it's a DB2 question?

Mark Storey-Smith

@ConcernedOfTunbridgeWells Core systems at my main contract are as400/db2/synon

I stay well away from them1

ConcernedOfTunbridgeWells

DB2/400, which is nominally DB/2 but architecturally integrated with the O/S.

@MarkStoreySmith I've worked a little with GENIUS, which is built on that platform.

jcolebrand

4:48 PM

So, as for should that be migrated here, no, that's purely a code Q

ConcernedOfTunbridgeWells

5:01 PM

Members in DB2/400 tables ring a bell at the back of my mind, but I can't put a finger on it. My google-fu isn't really getting far either.

jcolebrand

When you guys are advocating people to give better examples in their Q, check this resource (that I always forget about)

sscce.org

Mark Storey-Smith

Nice, bookmarked

gbn

5:56 PM

Do we have a name decision yet, now this place is busy

Data Gurus looks good...

JNK

6:07 PM

i like that one too

you mean for the site not the chat right?

gbn

yep

"the heap" is good for here

jcolebrand

I like Data Gurus

I just hope if adopted it can help us encourage over some NoSQL

JNK

yeah me too

i do want to learn more about nosql as well

gbn

If COTW can bring the BI folk in then we're well on the way to Data Gurus

Jack Douglas

6:25 PM

4

A: What kind of database/DBA questions does the SO community want to keep?

This question was asked on dba.se My accepted answer uses two levels of analytic (windowing) functions to get the desired result in a single SQL statement. Not all RDBMSs provide analytic functions but the question was specifically for Oracle which is one of those that do. If it had instead be...

I've been encouraging people to go vote this down if they don't like the idea this stuff would be migrated here

only fair that I should also ask anyone here who is active on SO to vote too (presumably up but whatever you think is best)

and hello and bye :-)

Ivo Flipse

Migration is a touchy subject, because the questions aren't necessarily off-topic for SO

So the problem to solve would be: how do we get SO users to recognize that DBA is a kick-ass place for their DB questions and that its more effective to get them answered here, rather than on SO

5

ConcernedOfTunbridgeWells

6:51 PM

@IvoFlipse Frustration with not getting cogent answers for database related questions because they get drowned out in all the .Net traffic?

That's why I proposed the Business Intelligence site, because of this class of problem

Ivo Flipse

@ConcernedOfTunbridgeWells That's an excellent reason for coming here rather than SO, much more focus

ConcernedOfTunbridgeWells

9

A: StackOverflow has become useless for me : |

I do notice a similar phenomenon - often I'm asking quite obscure questions. Generally, I can find answers on the web for most things, so by the time I'm asking something on SO it's something that can't easily be found by searching on the web. Obscure questions will suffer from the combination ...

@IvoFlipse Also, see the discussion question about whether the Business intelligence proposal should be merged into the DBA site.

Ivo Flipse

Interesting, I just watched the db-class video about OLAP

ConcernedOfTunbridgeWells

@IvoFlipse db-class video? Who publishes that?

Ivo Flipse

db-class.org

Jennifer Widom from Stanford, there are several other flavors at the moment like AI and Machine Learning. In January they'll have even more

6

Q: "Database Administrators" needs to die

Every few weeks another sharp poster asks: Why are you asking DBAs about source control? Why are you asking DBAs about performance? Why are you asking DBAs about database design or data warehousing? As a regular DBA.SE patron your response might be: "Because all of those topics are welcome on...

discussion site-definition

I feel your pain ^^

Fitness & Nutrition has the same problem, everyone thinks we're about weight lifters and food junkies

Nick Chammas

7:09 PM

@IvoFlipse your name alone does wonders for you image

on an unrelated note, there goes Rolando again trashing the homepage with trivial edits

Ivo Flipse

@NickChammas In what sense?

Nick Chammas

@IvoFlipse sorry I meant perception, not image

people already have thing associated with the name you use

Ivo Flipse

In what sense? :P

Nick Chammas

which may or may not coincide with the actual focus of the site

Ivo Flipse

Oh right, with F&N

Nick Chammas

7:10 PM

yeah

Ivo Flipse

Yes, I know that Sathya (the SU mod) was very disappointed that his questions 'didn't' belong here, which was rubbish, its just the perception that they didn't belong here

5

Q: Community Promotion Ads - 4Q 2011

What in the Wide, Wide World of Sports is Going On Here? TL;DR -- put images and links in the answers. If they get voted up enough, they will appear on the main site as community promotion ads. But whyyyyyyy? This is a method for the community to control what gets promoted to visitors on the s...

discussion community-ads

Perhaps you guys should post an ad here

that explains what questions you do want

though on second thought, it isn't used on other SE sites :(

scratch that

Nick Chammas

@jcolebrand @JackDouglas - What is the right thing to do with regards to Rolando and his mass trivial-editing? He's doing things like capitalizing words, adding one punctuation mark... things that are totally not critical. It's like he promised himself he'd get the Copy Editor badge before the end of the year.

not that I care about the badge; I care about the front page being completely swamped with his stuff

Ivo Flipse

There have been similar discussions about this on Meta.Superuser and Gaming, but the responses from the teams vary somewhat

If its really annoying and he does it consistently, then he could get a short suspension, but that's more of a last resort really. Other than that the mods can contact him privately to ask him to restrain himself from flooding the frontpage with edits. Your only option is to raise the issue on Meta and come up with a solution everyone can live with

gbn

7:59 PM

comments on this?

0

What would be a good way to calculate the recommended minimum hardware configuration for a Windows 2008 R2 64bit that will be running SQL Server 2008 R2 Analysis and Reporting Services? The database server is on another machine. The current configuration is : Virtual Machine running on a vmwar...

sql-server-2008 reporting-services

Simon Righarts

@gbn: zero-thought answer is "there should be something on BOL for that"

gbn

@SimonRigharts I was more thinking of OP's situation too

Simon Righarts

8:15 PM

I know nothing about SSRS/SSAS, but wouldn't the complexity of the reports/analysis you want to do factor into the specs as well?

gbn

@SimonRigharts yeah, I added a further comment.

Nick Chammas

8:33 PM

@gbn do you have a LinkedIn page or some non-SE place where I can contact you?

Simon Righarts

10:26 PM

Is Rolando making it his personal mission to edit every question on the site? Re-tagging and minor edits on fresh questions I can understand but there's some serious gold-plating of old questions, e.g.

dba.stackexchange.com/posts/3942/revisions

Ivo Flipse

@SimonRigharts I suggest bringing it up on Meta if everybody is getting annoyed by it

Simon Righarts

as a general guideline on editing posts, you mean?

Ivo Flipse

Well at least about the frequency and how trivial they may be

Jack Douglas

10:48 PM

@NickChammas I just took a look at a bit of his recent activity - it includes answering Qs and some trivial edits. I think he just likes to make all his contributions in batches :) Yes the trivial edits are unnecessary, I highly doubt he is doing anything other than trying to help though. I think the friendly thing to do would be to have a arm-round-the-shoulder quiet word rather than calling him out on meta or whatever

which I will do

Simon Righarts

I think a reasonable guideline is that if a question is off the front page (then it's gone by a bunch of other people without them seeing the need to edit it) then editing is generally unnecessary

that's just my take on it though

Jack Douglas

@SimonRigharts IMO that's a bad guideline

we want good edits and anyone willing to improve any post however old should be applauded

problem here is that some of the edits don't add value

stupid question coming up, do you know SQLKiwi aka Paul White?

Simon Righarts

thinking about it a little bit more you're right

and no I don't, I'm relatively new to the DB business

also, contrary to popular belief, we don't actually know every other new zealander ;)

Ivo Flipse

Hi @JackDouglas guess what I'm doing right now ;P

Jack Douglas

@SimonRigharts haha

I told you it was a stupid question

@IvoFlipse I'm slightly afraid to guess - does it involve a computer game or a database?

Ivo Flipse

10:56 PM

Its a database

Simon Righarts

seems like the day for it, just had someone wander past looking for a person that was in the next cube ... three months ago

Ivo Flipse

Need to write triggers again, while the previous three questions went reasonably well, I now have to combine those three and that process isn't going too well :(

Simon Righarts

the actually stupid part is that our online phonebook isn't updated

Jack Douglas

@IvoFlipse new question?

oops scrolling fat fingers

Ivo Flipse

We have this Movie ratings database and have to update views using triggers

Simon Righarts

11:01 PM

update .. views? I don't get it

Ivo Flipse

And my stupid query does most of the stuff right, except for the ratings (last column)

> Each of the problems asks you to enable a certain type of modification to one of the views by writing an "instead-of" trigger. Each question contains a link to a View-Update Workbench, which will help you develop and debug your instead-of triggers. The workbench creates your trigger using SQLite on the original state of the sample database. It then issues a modification statement on the view, which should activate your trigger to modify the base tables accordingly.

Jack Douglas

@SimonRigharts sqlite.org/lang_createtrigger.html#instead_of_trigger

Simon Righarts

oh, a trigger to make views updatable, that makes more sense

sorry, I'm doing space usage projections and my brain just isn't in the zone at the moment

Jack Douglas

Hey Oracle can update a view if is is key-preserved asktom.oracle.com/pls/asktom/…

without a trigger :)

Ivo Flipse

Oh darn, hold that thought @JackDouglas I have to go pick up my GF from work :\

and I think someone on the DB-class Q&A forum had the same problem + a suggestion for a solution

Jack Douglas

11:04 PM

@IvoFlipse ha

Ivo Flipse

> You have to distinguish, in the Rating update the tuples where you need to update only the mID and those where you need to update both mId and stars.

Jack Douglas

see you later

Ivo Flipse

No idea what that means (yet), but we'll see

Jack Douglas

11:18 PM

@NickChammas we've chatted about it and Rolando will bring it up on meta - that is the best place to get guidelines for the site together

Nick Chammas

11:34 PM

@JackDouglas cool

today's volume was excessive

if he want to discuss it then sweet

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