So you are quite limited on how to store SQL data, and on changing the physical schema without changing the logical and user ones.
Well yes, but to be able to change the relationship of the data (ie: table dependancies, column names, keys) WITHOUT the application even knowing that the change had been made means that you need to add an abstraction layer between the application and the data. This already exists in multi-tier models.
But you still need to be able to converse with the data base engine at some level. So your data access layer must have an understanding of the data storage schema. Whether you are using an RDBMS, flat file system, or OO system, somewhere along the line the data in the file becomes data in RAM, and becomes organized in such a way that the application can use it.
Using SQL means that you are using a standards based language to converse with the data base engine. Because computers are stupid, care must be taken to ensure that data integrity is not lost. Whether this happens at the application level, data level, or through some RDBMS engine is only relevant to whomever is responsible for the integrity.
It would be nice to be able to specify ALL of this in the data base engine, but it still needs to be retrieved. And the retrieval system must have an understanding of what it is retrieving so it can package it for the application (and vice versa).
That is actually a bad example. Not only SQL itself prevents real data independence, if one mixed a relational language (that SQL is not) to any non-relational language to access a particular database, one looses the relational data independence because the non-relational access will have assumptions on the database physical schema and access plans.
I was pointing out that SQL is only one way to get at the data. Yes, extreme care must be taken to ensure that data dependancies are not violated (and probably in more places). But then a DBA must do the same when they set up dependancies in the data schema. The main difference is the level at which data dependancy is conserved. I agree that it is MUCH better to set up the dependancy checking lower down. All higher level code is then forced to comply with it.
I jumped into this discussion because the real problem is the way that we store information, not the particular way we get at it. Columns, rows (collections of columns), tables (collections of rows and columns) are all terribly limiting. You must carefully partition the information, try to figure out the owner of each piece of information, then apply strict rules so someone does not break your view of the information. This is known as a data schema.
Then someone comes along and tells you that you forgot something. Now your schema is wrong, and you must change it, and the application which acts on the information must be changed. Oops!
Until we can store, retrieve, and process information in a homogenous fashion we will have these problems.
Isn't SQL just a language which converses with a database engine? So the underlying structure of the database engine is not relevant?
You can have an engine that actually stores the information in a fixed length field text file, then uses SQL to extract information from that file. Slow? Yup, but SQL can still be used.
Case in point is FOXPRO. You can use either SQL or the xBase language to get at the information. In the same code file.
More important to follow the "budget" than to save money!
There was a multi-million contract to repair the sewers. Next year the budget called for repairing the water line. Both sewer and water line were routed down the middle of the street.
To repair the sewer the contractor ripped up the street, dug down, and repaired the sewer. While he was down there he noticed that the water line had also been exposed.
He went back to the owner and said: "For a few dollars more I can fix the water line".
The answer? No WAY. The sewer contract used up this years budget and there is no money.
Saving pennies, throwing away dollars.....
Um yes, this was a government contract. Your tax dollars at work.
Re:Sometimes, and it can cause problems too.
on
Linux Kernel Code Humor
·
· Score: 3, Informative
I understand this. But it still CAN be re-constructed. There is a person within the intelligence community whose job it is to verify shredders. You put a blank sheet through, clean the rollers and cutting blades, then pass though a test sheet. This sheet is then collected in its entirety in a bag and send to this person. They then try to re-assemble the test sheet. Consequently I trust very few shredders.
And the shredder I am talking about has a security rating of TOP SECRET. It cuts and cross cuts, with the resulting cut sized about one/half millimeter by 4 millimeters. This shredder I trust.
ashes are intact
Not after I get through mixing them around, burning wood with them, and pouring water on the fire. I do this once a year on the annual camping trip.
A wee bit late.... (Score:1) by lgftsa (617184) Alter Relationship on 2002.12.31 17:14 (#4991804) It's 12:09pm 1/1/2003 here. This story is about 15 hours overdue.
Does anybody remember the OS/2 Warp (3.0) system web browser?
I do.
It had a complete Web page showing all the links and hyper links that you visited.
The first page was at the root level, then each link from that page was nested, with each subsequent link nested in turn. Each link was shown with the page title and was a link so you could re-visit that page.
After a few hours it was interesting to see your browsing process. First you were here, then you went there, and there, and...
I miss that feature. It showed Web browsing in a non-linear fashion.
It is OO fans who love it and the rest who say "whatever".
If you have done any serious programming over any real length of time, you tend to do OO programming whether you call it that or not.
Grouping variable names using a prefix, allocating and initializing structures using a function, operating on those structures using well defined functions, etc.
These are OO concepts without the formal OO architecture.
That would mean that I am legally compelled to look at EVERY piece of advertising that some company wants to push at me. I cannot change channels, I cannot flip by magazine ads, I cannot close my eyes,...
Show me a law that compells me to look at advertising. Just because a company spends money on something, does not mean that I have to submit to it.
As someone involved in advertising for a major newspaper
Hi.
I am exposed to so much advertising in my daily life, that NO advertising works on me. Between Web ads, spam, newspaper ads, tv ads, billboards, radio ads, planes flying overhead with banners, etc, my eyes are exposed to a LOT of companies trying to tell me about their products.
I look, but I do not see.
I have so trained my eyes and my brain to filter out this kind of junk that you are wasting your time. Take the ads that appear with the slashdot stories. I do not know what they are. My eye (and my scrollable mouse finger) just brush past it.
And TV ads? Forget it. That is what the remote if for, MUTE and click on to another channel. I have not watched an ad on TV for many years.
I HAVE noticed that they take up more time, but soon my brain will be used to the new junk interval (I amaze my friends by being able to click around, then suddenly go back to the show just as the ads end).
Ignore it, destroy it if you can't stand it and get on with life outside spam.
I have a filter that finds the spam, and replies to it (using a trash basket return email address) with the body saying something like "go away, no one wants this nor read this".
If the reply address is a bogus email address, then the ISP response of no valid email address is deleted. If I get one to the trash basket it is deleted.
Ok, sure it increases TCP traffic, but it sends it back to the source. If we ALL did this, then the senders of spam would get, well, spammed.
Id rather have inconsistant syntax and a powerful, efficient build system than the consistant syntax any day.
Huh?
You must like Visual Basic then. It has the most inconsistent syntax going. And it was built in an adhoc make-it-up-as-you-go fashion.
There is no excuse for sloppy syntax structure. Take the time to make it right. Otherwise you end up with a mess of things the programmer has to remember, AND it becomes a nightmare to maintain.
Slashdot Mirror
Sort of like a 300 baud MODEM.
Read the words as it came over the line.
you can no longer do a low level format on a drive.
You can on SCSI drives. Through the SCSI controller BIOS.
The first hard drive I bought cost me $500.
It was a 10 MByte (yes, that's mega) Seagate. Full height 5 1/4 (hint, a CD drive is half height).
I partitioned it into 4 drives:
C: 1M - DOS (V 2.0 !)
D: 4M - Applications
E: 4M - Data
F: 1M - Testing
Mind you after struggling with two 5 1/4 floppy drives, this was heaven.
I still have it, after all, where could I possibly sell it?
So now you can punch the monkey, and it gives you a drink.
And if you are two drunk to punch the monkey, you need to go home.....
So you are quite limited on how to store SQL data, and on changing the physical schema without changing the logical and user ones.
Well yes, but to be able to change the relationship of the data (ie: table dependancies, column names, keys) WITHOUT the application even knowing that the change had been made means that you need to add an abstraction layer between the application and the data. This already exists in multi-tier models.
But you still need to be able to converse with the data base engine at some level. So your data access layer must have an understanding of the data storage schema. Whether you are using an RDBMS, flat file system, or OO system, somewhere along the line the data in the file becomes data in RAM, and becomes organized in such a way that the application can use it.
Using SQL means that you are using a standards based language to converse with the data base engine. Because computers are stupid, care must be taken to ensure that data integrity is not lost. Whether this happens at the application level, data level, or through some RDBMS engine is only relevant to whomever is responsible for the integrity.
It would be nice to be able to specify ALL of this in the data base engine, but it still needs to be retrieved. And the retrieval system must have an understanding of what it is retrieving so it can package it for the application (and vice versa).
That is actually a bad example. Not only SQL itself prevents real data independence, if one mixed a relational language (that SQL is not) to any non-relational language to access a particular database, one looses the relational data independence because the non-relational access will have assumptions on the database physical schema and access plans.
I was pointing out that SQL is only one way to get at the data. Yes, extreme care must be taken to ensure that data dependancies are not violated (and probably in more places). But then a DBA must do the same when they set up dependancies in the data schema. The main difference is the level at which data dependancy is conserved. I agree that it is MUCH better to set up the dependancy checking lower down. All higher level code is then forced to comply with it.
I jumped into this discussion because the real problem is the way that we store information, not the particular way we get at it. Columns, rows (collections of columns), tables (collections of rows and columns) are all terribly limiting. You must carefully partition the information, try to figure out the owner of each piece of information, then apply strict rules so someone does not break your view of the information. This is known as a data schema.
Then someone comes along and tells you that you forgot something. Now your schema is wrong, and you must change it, and the application which acts on the information must be changed. Oops!
Until we can store, retrieve, and process information in a homogenous fashion we will have these problems.
Isn't SQL just a language which converses with a database engine? So the underlying structure of the database engine is not relevant?
You can have an engine that actually stores the information in a fixed length field text file, then uses SQL to extract information from that file. Slow? Yup, but SQL can still be used.
Case in point is FOXPRO. You can use either SQL or the xBase language to get at the information. In the same code file.
More important to follow the "budget" than to save money!
There was a multi-million contract to repair the sewers. Next year the budget called for repairing the water line. Both sewer and water line were routed down the middle of the street.
To repair the sewer the contractor ripped up the street, dug down, and repaired the sewer. While he was down there he noticed that the water line had also been exposed.
He went back to the owner and said: "For a few dollars more I can fix the water line".
The answer? No WAY. The sewer contract used up this years budget and there is no money.
Saving pennies, throwing away dollars.....
Um yes, this was a government contract. Your tax dollars at work.
a tie is a most useless piece of cloth
History of the tie
especially if they use the rotating cutter method
I understand this. But it still CAN be re-constructed. There is a person within the intelligence community whose job it is to verify shredders. You put a blank sheet through, clean the rollers and cutting blades, then pass though a test sheet. This sheet is then collected in its entirety in a bag and send to this person. They then try to re-assemble the test sheet. Consequently I trust very few shredders.
And the shredder I am talking about has a security rating of TOP SECRET. It cuts and cross cuts, with the resulting cut sized about one/half millimeter by 4 millimeters. This shredder I trust.
ashes are intact
Not after I get through mixing them around, burning wood with them, and pouring water on the fire. I do this once a year on the annual camping trip.
I'm in Sydney and we have been in 2003 for the last 12 hours.
Well get drinking then, man. You have another twelve glasses to go.....
A wee bit late.... (Score:1)
by lgftsa (617184) Alter Relationship on 2002.12.31 17:14 (#4991804)
It's 12:09pm 1/1/2003 here. This story is about 15 hours overdue.
Nope, you are 6+ hours early.
Adjusted for my timezone that is....
I burn my personal trash.
Credit Card receipts, income statements, bank statements, etc.
I do NOT trust shredders unless they produce dust, and those are expensive. The Office Depot shredders are a joke.
Does anybody remember the OS/2 Warp (3.0) system web browser?
...
I do.
It had a complete Web page showing all the links and hyper links that you visited.
The first page was at the root level, then each link from that page was nested, with each subsequent link nested in turn. Each link was shown with the page title and was a link so you could re-visit that page.
After a few hours it was interesting to see your browsing process. First you were here, then you went there, and there, and
I miss that feature. It showed Web browsing in a non-linear fashion.
It is OO fans who love it and the rest who say "whatever".
If you have done any serious programming over any real length of time, you tend to do OO programming whether you call it that or not.
Grouping variable names using a prefix, allocating and initializing structures using a function, operating on those structures using well defined functions, etc.
These are OO concepts without the formal OO architecture.
And this from an AC ....
not watching ads is stealing
...
Bullshit!
That would mean that I am legally compelled to look at EVERY piece of advertising that some company wants to push at me. I cannot change channels, I cannot flip by magazine ads, I cannot close my eyes,
Show me a law that compells me to look at advertising. Just because a company spends money on something, does not mean that I have to submit to it.
As someone involved in advertising for a major newspaper
Hi.
I am exposed to so much advertising in my daily life, that NO advertising works on me. Between Web ads, spam, newspaper ads, tv ads, billboards, radio ads, planes flying overhead with banners, etc, my eyes are exposed to a LOT of companies trying to tell me about their products.
I look, but I do not see.
I have so trained my eyes and my brain to filter out this kind of junk that you are wasting your time. Take the ads that appear with the slashdot stories. I do not know what they are. My eye (and my scrollable mouse finger) just brush past it.
And TV ads? Forget it. That is what the remote if for, MUTE and click on to another channel. I have not watched an ad on TV for many years.
I HAVE noticed that they take up more time, but soon my brain will be used to the new junk interval (I amaze my friends by being able to click around, then suddenly go back to the show just as the ads end).
So you and your ilk can go pound sand.
Could you imagine the uproar if every bullet in America had to be registered with the government?
.22 bullet. It would be impossible to fit the serial number on it.
Well, it would eliminate the
Ad revenues fall, and cable companies go bankrupt.
More like: Ad revenues fall, shows cannot pay actors stupid amounts of money.
Well yes, except that you NEED a base of operations in space to do the elevator.
Ignore it, destroy it if you can't stand it and get on with life outside spam.
I have a filter that finds the spam, and replies to it (using a trash basket return email address) with the body saying something like "go away, no one wants this nor read this".
If the reply address is a bogus email address, then the ISP response of no valid email address is deleted. If I get one to the trash basket it is deleted.
Ok, sure it increases TCP traffic, but it sends it back to the source. If we ALL did this, then the senders of spam would get, well, spammed.
Name calling? That promotes discussion...
The point was that sloppy syntax is a BAD THING, giving VB as a prime example.
I have nothing against Ant. I just hate inconsistent, sloppy architecture.
Id rather have inconsistant syntax and a powerful, efficient build system than the consistant syntax any day.
Huh?
You must like Visual Basic then. It has the most inconsistent syntax going. And it was built in an adhoc make-it-up-as-you-go fashion.
There is no excuse for sloppy syntax structure.
Take the time to make it right. Otherwise you end up with a mess of things the programmer has to remember, AND it becomes a nightmare to maintain.
Yes of course. And while the farmers are busy growing food and surviving, the rest of the human race will just willingly lay down and die, right?
...
The rest? No, just most.
Modern agriculture is very dependant on the rest of us continuing to function. Weather reports, fuel, distribution, fertilizer,
Re your sig "How come we choose from just two people to run for president and fifty for Miss America? ".
Because the job of Miss America is more important and carries more prestige.