The Heap™ – Consultancy ©®

Ben Brocka

11:34

Amazon releases NoSQL Dynamo DB

Ben Brocka

14:12

1

A: Should our FAQ draw a line for "DBA" SQL questions and "SO" SQL questions? Is there one?

I think this is a great idea -- if you haven't already, I suggest a diamond mod editing this addendum into the DBA FAQ. http://dba.stackexchange.com/faq I do see but this is not the right place to ask questions about... client-side programming (ask on Stack Overflow instead) basic...

jcolebrand

15:19

facebook.com/ronpaul/posts/10150536046641686

whoa whoa whoa, what?

I'm curious to see what the outcome of this is

Ben Brocka

> Hope he doesn't have something dangerous on him like a copy of the constitution

Heh

ConcernedOfTunbridgeWells

Can't see this through the firewall. What's he just done?

jcolebrand

Ron Paul
My son Rand is currently being detained by the TSA at the Nashville Airport. I'll share more details as the situation unfolds.

As far as I've ever been able to tell, that's about the most clean young man in Congress

Ben Brocka

I'm sure he's fine. Your chance of being detained by the TSA is inversely proportional to your chance of actually being dangerous best I can tell

jcolebrand

15:40

My son @SenRandPaul being detained by TSA for refusing full body pat-down after anomaly in body scanner in Nashville. More details coming.

Tweeted by RonPaul on January 23, 2012 at 3:22 PM

@BenBrocka except when you refuse patdown

Ben Brocka

People who refuse patdowns are at least 99.9% people who have read the 4th amendment rather than terrorists. To date I'm not aware of their "enhanced patdowns" actually finding anything

Jack Douglas

15:57

@ConcernedOfTunbridgeWells hello :-)

jcolebrand

We have a proposition for you lot here

922

Q: FAQ for Stack Exchange sites

Community FAQ For sites in the Stack Exchange 2.0 network To see a list of commonly used words and phrases, see the glossary. Content Asking questions How do I write a good title? How to ask a smart question? How can I get answers fast? Is there a limit on how many questions I can ask? ...

If you're not familiar with this Q, it might be a good idea for you to peruse it

Jack Douglas

After the BI merge we thought it might be good to have our own version here, linked to by the faq, with more detailed information about what we want migrated, what "DBA" really means etc etc :-)

jcolebrand

Give us a chance to break things down neatly, with a simple link from the FAQ, allow us to keep the FAQ as clean as it is now

Also, everybody should watch this ted.com/talks/…

ConcernedOfTunbridgeWells

@JackDouglas Hi

Jack Douglas

16:20

@ConcernedOfTunbridgeWells thought you might be interested in this conversation :-)

Nick Chammas

16:34

I love you guys.

jcolebrand

For what?

Mark Storey-Smith

infoworld.com/d/security/…

Nick Chammas

This problem is why I prefer Oracle mandating all SQL statements terminate with a semicolon.

@jcolebrand Just in general. Thought I'd say that in case I died suddenly.

jcolebrand

@NickChammas lmao, ok

I love you too man

Jack Douglas

@NickChammas do you also find us amusing ;-)

@NickChammas Oracle doesn't mandate that btw :-)

Nick Chammas

16:44

@JackDouglas I find you add value to my day in many forms, among them certainly is amusement.

Jack Douglas

but I know what you mean

Nick Chammas

@JackDouglas No?

Jack Douglas

eg in SQL Developer you need a ; between statements but if you only have one statement it doesn't need it

it's a client tool thing rather than a database thing anyway...

Nick Chammas

@JackDouglas yeah, certainly; in that user's case, the two statements would have been interpreted as one and caused a syntax error

if that was on oracle

instead, the poor guy emptied his table

jcolebrand

technically doesn't the SQL spec require a semicolon between queries (even contiguous ones) and the engine parsers are just smart enough to generally know where semicolons belong?

or at least, the grammar

Nick Chammas

16:47

@jcolebrand yah, that's how SQL Server rolls

but MS is warning everybody to start using semicolons because they will become mandatory

Jack Douglas

@NickChammas nasty. like when I pressed F5 in SQL Developer again the other day after messing around with SSMS.

not blaming SSMS mind

PICNIC

Nick Chammas

msdn.microsoft.com/en-us/library/ms177563.aspx?ppud=4

> ;
> Transact-SQL statement terminator.Although the semicolon is not required for most > statements in this version of SQL Server, it will be required in a future version.

jcolebrand

@JackDouglas problem in compiler, not in chair, I agree

Nick Chammas

that's what that means?

lol

Jack Douglas

@jcolebrand you are too kind :-)

jcolebrand

16:50

@NickChammas it means "Problem In Chair, Not In Computer" ;-)

I prefer PEBKAC

Jack Douglas

@NickChammas no

jcolebrand

Problem Exists Between Keyboard And Chair

Nick Chammas

aaaaaaaaaaaahhhhhhhh

Jack Douglas

oops too slow

Nick Chammas

PEBKAC is the one I've heard

@MarkStoreySmith on page 3 now... wtf

Mark Storey-Smith

16:55

@NickChammas Scary stuff!

Jack Douglas

@MarkStoreySmith nobody uses ALTER DATABASE BEGIN BACKUP though

that's ancient history

the whole article is overblown hype IMO

Mark Storey-Smith

@JackDouglas You still went and checked your SCNs though didn't you? :)

Jack Douglas

you're kidding - this is a DW, we get about one SCN per minute :-)

5170830546

Mark Storey-Smith

230 trillion odd to go for you then!

Jack Douglas

17:10

ha ha :-)

Mark Storey-Smith

From what I understand from the article, the problem is really confined to very large deployments with linked systems right? As the SCN is cascaded between linked databases?

Nick Chammas

omg

2

Q: Is my bank storing my password in plain text?

My bank (and every bank I've come across) only ever asks for individual characters from my password when logging in. Is my bank storing my password in plain text?

passwords

Jack Douglas

@MarkStoreySmith They are saying if you use an obsolete method of backing up your database deliberately in an RAC cluster there is an outside chance of an intractable problem. To me it looks like "if someone evil has access to one of your databases he could sabotage them" - which is kind of a truism.

Mark Storey-Smith

@NickChammas The two UK banks I use, 2 cc providers and investment platform I use all do this

jcolebrand

ALTER procedure [dbo].[Dash_ControllableExpenses]

as

select
	'2009-11-30' EndingDate
	,200000.00 MonthlyExpense
	,1800000.00 YTDExpense

That is the completeness of this query

WTF?

Nick Chammas

17:15

@jcolebrand no bugs in that baby

jcolebrand

@NickChammas no documentation either

Nick Chammas

@MarkStoreySmith isn't this a bad, bad sign for their industry?

jcolebrand

I'm not even sure where the hell to look to see what it's for

Mark Storey-Smith

@NickChammas The answer from jimbob covers why its used, to prevent replay attacks

Nick Chammas

@MarkStoreySmith this is good question :)

Jack Douglas

17:17

It's just picking on the poor sad lonely Oracle people ;-)

Nick Chammas

@MarkStoreySmith don't see why it needs to be reversible encryption

ConcernedOfTunbridgeWells

@JackDouglas Do you want to rephrase the FAQ in terms of a series of questions (per a traditional FAQ) with links out to deeper discussions of the individual questiions?

Nick Chammas

you have hashes for all (n choose 3) possible combinations; why should they be reversible?

ConcernedOfTunbridgeWells

And maybe add summary answers to the questions, e.g.

Are questions about reporting tools in scope for this site: Yes (with a link out to a meta question that discusses it in some depth).

Mark Storey-Smith

@NickChammas Not an expert on such matters but I guess that by storing hashes for a combination of 3 character combinations, it becomes viable to brute force the hashes

Nick Chammas

17:23

@MarkStoreySmith I'd like to know how that is. Just asked the dr

@JackDouglas 3,711,639,348

Jack Douglas

@ConcernedOfTunbridgeWells no nothing that drastic - just add a brief subsection at the end of the top section of the faq with a link to a meta Q like the one on mSO Cole linked

@NickChammas thats potentially a lot of combinations ;-)

Nick Chammas

18:00

@JackDouglas - answer updated to include max SCN

Jack Douglas

@NickChammas but I held off on my downvote anyway ;-)

Nick Chammas

@JackDouglas lol

i hit submit and then I was like, wait... I didn't answer my own question completely

if anybody knows how to pull the SCN for <9i versions of Oracle, please add your answer

Jack Douglas

Anyone know if SS or other RDBMS can do select distinct pk_leading_column without a full scan?

Nick Chammas

you're talking about a multi-part PK

?

Jack Douglas

18:18

@NickChammas yes that's what I mean

but I'm not really talking about keys - just whether the optimizer can use leading columns of an index (including non-unique index) to do a distinct assuming all are not null.

I am not good at communicating my thoughts :-)

related to comments on an answer of mine here

atxdba

19:01

altering events, even alter event evt_name enable; causes it to become disabled on slaves. kinda WTF IMO

JNK

19:22

@JackDouglas it's going to be a clustered index scan no matter how you dice it I think. It needs to read the whole clustered index but I think it can use the stored metadata to get those distinct values more quickly

@JackDouglas - just confirmed. I made two 3-column tables, all fields are varchar(10), with identical 1m rows each. I indexed table 1 on A,B and table 2 on B,a. SELECT DISTINCT ColA runs in around half the time, with half the CPU, on the one with the index on that field FIRST. Opposite holds true as well for SELECT DISTINCT ColB

Nick Chammas

@JNK cool

Nick Chammas

21:22

is this guy right?

27

A: Is there any reason to worry about the column order in a table?

Column order had a big performance impact on some of the databases I've tuned, spanning Sql Server, Oracle, and MySQL. This post has good rules of thumb: Primary key columns first Foreign key columns next. Frequently searched columns next Frequently updated columns later Nullable columns last...

jcolebrand

the edit is right

> EDIT: Sql Server 2005 stores fixed-length fields at the start of the row. And each row has a reference to the start of a varchar. This completely negates the effect I've listed above. So for recent databases, column order no longer has any impact.

modern engines know how to fix screw ups, same as compilers

Nick Chammas

oh whoops, yup

that's what I though

Nick Chammas

21:49

for those of you using C#

0

Q: How do I keep my stored procedure inputs from being silently truncated?

We use the standard System.Data classes, DbConnection and DbCommand, to connect to SQL Server from C#, and we have many stored procedures that take VARCHAR or NVARCHAR parameters as input. We found that neither SQL Server nor our C# application throws any kind of error or warning when a string lo...

c# sql-server stored-procedures error-handling

Simon Righarts

23:20

morning chaps

we don't have any Sybase experts kicking around, do we?

Nick Chammas

23:35

there's this guy I know who lurks on here

his name is Simon Righarts

he knows some Sybase

Simon Righarts

Haha. Was looking for an expert, not the village idiot. :D

2

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