Normalization
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CHill60 wrote:
I'm stuck with what was someone else's idea of Good Database Structure
That's why we normalize. One of my "betters" once introduced a table that held a varchar(31) with 0's and 1's. Representing booleans. Queries where horrid and slow.
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
Eddy Vluggen wrote:
ntroduced a table that held a varchar(31) with 0's and 1's.
I had a colleague who used 1s and 8s -- because he couldn't get 0s to work correctly. :sigh:
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I would if I could. :-D In fact, I do as much as I can, which is limited and not always beneficial. But the issue is that my current primary task is simply ETLing data from various sources to our staging database. For that, it's usually best to just leave it as is. But, at times, I do split some data into child tables -- usually if the incoming data has been de-normalized such that a field contains delimited lists of values (yuck). It really depends on the needs of the next layer of the overall application, which often requires de-normalized data anyway. On those rare occasions when I create a database for a "proper" application, I normalize as required for the application. But I don't care about the definitions of the various normal forms; I leave that to the ivory tower types.
PIEBALDconsult wrote:
But I don't care about the definitions of the various normal forms; I leave that to the ivory tower types.
They're not under debate in the tower. The definitions didn't change. It's not C#.
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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On the data entry / operational side, always; on the informational / query side, usually the opposite. Storage is cheap; time isn't.
It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it. ― Confucian Analects: Rules of Confucius about his food
This about how to store. No difference in entry or query.
Gerry Schmitz wrote:
Storage is cheap; time isn't.
Time is not a factor here; this is about being correct. As in, making sure the data you return is correct. It also not just applies to databases, but is general theory about information. Even applies to some lists, or dictionaries :)
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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Eddy Vluggen wrote:
ntroduced a table that held a varchar(31) with 0's and 1's.
I had a colleague who used 1s and 8s -- because he couldn't get 0s to work correctly. :sigh:
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I do. That's why I had to look it up. I never learned it formally. I just learned "construct a database in a way that maintains integrity and is sane enough for the application to survive for awhile"
Real programmers use butterflies
honey the codewitch wrote:
I do. That's why I had to look it up. I never learned it formally.
It does sound like I'm attacking. My apologies.
honey the codewitch wrote:
construct a database in a way that maintains integrity
You'd laugh and go "that's soo obvious".
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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honey the codewitch wrote:
I do. That's why I had to look it up. I never learned it formally.
It does sound like I'm attacking. My apologies.
honey the codewitch wrote:
construct a database in a way that maintains integrity
You'd laugh and go "that's soo obvious".
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
I didn't take it as an attack, no worries. I figured I just needed to clarify. I learned DBs in the .com boom days when it was a free for all. I attempted to impose some order on the mess. All I got for my efforts typically was put in charge of databases - something i didn't want to be in charge of. And then there was the time when I worked with a self taught developer who built out an entire ecommerce platform, front and back end, including a jquery-like (but *not jquery :~ :mad:) engine for the front end. Rather than doing JOINs in the database he was doing them in PHP on the webserver. I taught him SQL. Then I quit.
Real programmers use butterflies
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That's true, and given the amount of space to work with that we have these days, and how good databases are at doing batch data conversion and such, there really isn't a good reason to avoid redundant data if it makes things easier or more efficient. You just have to be careful not to go crazy with it, and you have to keep in mind that it can make your database more "brittle" because its more fields that need to be proofed/validated for correctness. Keeping redundant data in sync is a chore unto itself. But yes yes yes to this. Redundant data is okay, when it serves a purpose, often for performance or integration purposes it is The Right Way(TM) to do things. And if I'm wrong then I got paid a whole lot of money to be wrong, and a lot of people happy with how wrong I was. :laugh:
Real programmers use butterflies
honey the codewitch wrote:
The Right Way(TM) to do things.
Math.
honey the codewitch wrote:
And if I'm wrong then I got paid a whole lot of money to be wrong
Yeah. Happy my surgeon isn't like that :thumbsup:
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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How many here normalize their databases?
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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How many here normalize their databases?
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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Is your name Marty Feldman?
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honey the codewitch wrote:
The Right Way(TM) to do things.
Math.
honey the codewitch wrote:
And if I'm wrong then I got paid a whole lot of money to be wrong
Yeah. Happy my surgeon isn't like that :thumbsup:
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
Eddy Vluggen wrote:
Math.
NoMATH (for clarity, Not Only Math) :rolleyes: Actually, that math was failing with big enough datasets, which is why NoSQL was (re-)invented. So the right way to do things went from "normalize everything" to "denormalize a good bunch." We've seen the opposite happen to peanut butter.
Best, Sander Azure DevOps Succinctly (free eBook) Azure Serverless Succinctly (free eBook) Migrating Apps to the Cloud with Azure arrgh.js - Bringing LINQ to JavaScript
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When you're talking about redundant storage, are you referring to data aggregated from single points of origin or an uncontrolled mess?
Wrong is evil and must be defeated. - Jeff Ello
Why not both? :laugh: But seriously, what starts out as the first sometimes turns into the latter :^) Mostly the first though :)
Best, Sander Azure DevOps Succinctly (free eBook) Azure Serverless Succinctly (free eBook) Migrating Apps to the Cloud with Azure arrgh.js - Bringing LINQ to JavaScript
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Sander Rossel wrote:
In the age of microservices every service needs to have the data it needs to do its thing.
Good point, those use a smaller dataset.
Sander Rossel wrote:
So I now even have multiple databases with the same data because multiple services operate on that data.
Operating implies you doin' more than reading that data.
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
Eddy Vluggen wrote:
Operating implies you doin' more than reading that data.
It's mostly reading and transforming. Not like, changing the data and then posting it back to its origin or something like that, that would be chaos.
Best, Sander Azure DevOps Succinctly (free eBook) Azure Serverless Succinctly (free eBook) Migrating Apps to the Cloud with Azure arrgh.js - Bringing LINQ to JavaScript
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How many here normalize their databases?
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
I've been coding for database interaction all my adult life - since the late 80s, and I've never heard of normalization so I looked it up and I'm aghast. How can you even use a database that isn't normalized? Why would you bother? Help me out here; where are these databases and what uses do people make of them?
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I've been coding for database interaction all my adult life - since the late 80s, and I've never heard of normalization so I looked it up and I'm aghast. How can you even use a database that isn't normalized? Why would you bother? Help me out here; where are these databases and what uses do people make of them?
Cpichols wrote:
Help me out here; where are these databases and what uses do people make of them?
The sad answers to your questions are "everywhere" and "a mess". Visualize a purchasing system where general customer information is free text. Further visualize trying to produce a sales report where a customer name may be spelled "ABC Trucking LLC", "ABC Trucking", "ABC Trucking Inc", and to make it really entertaining, " A B C Trucking " or " ABC Trucking" (application doesn't trim input and white space is significant). On the plus side, working with a system like this will make anyone an expert in regex ... :laugh:
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Cpichols wrote:
Help me out here; where are these databases and what uses do people make of them?
The sad answers to your questions are "everywhere" and "a mess". Visualize a purchasing system where general customer information is free text. Further visualize trying to produce a sales report where a customer name may be spelled "ABC Trucking LLC", "ABC Trucking", "ABC Trucking Inc", and to make it really entertaining, " A B C Trucking " or " ABC Trucking" (application doesn't trim input and white space is significant). On the plus side, working with a system like this will make anyone an expert in regex ... :laugh:
Okay then. While I do love a good regex puzzle, I'm thinking that maybe it's best to use selection menus built from a tight db. The db I work with was brilliantly designed, but does lack the level of normalization (ooh! look at me using this word in this new-for-me way! lol) that I would prefer, but it's pretty close for all that. I'd add one more layer, iah.
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How many here normalize their databases?
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
A wise man told me once: normalize till it hurts, then denormalize until it works. My app are mostly transactional and I don't see any other way then to have denormalized data.
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How many here normalize their databases?
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
I usually do not unless it is specifically requested by the project/boss because I tend to favor performance over conformance to normalization. To avoid data duplication or making a messy DB, I rely on my instinct and experience designing databases. But my DBs (for production) are usually built in layers and normalization only applies to the bottom (data) layer. On top of that are usually performance layers like "history request cache" for each client, cached queries (for full/partial queries that are required by other queries, usually per client), filters for queries (usually temporary tables with partial data), etc. And, before someone asks, yes those layers are implemented in the database (using SQL) where data is readily available and protected. And time is not wasted transferring data to some app while, in the process, creating a vulnerability in the database.
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I didn't take it as an attack, no worries. I figured I just needed to clarify. I learned DBs in the .com boom days when it was a free for all. I attempted to impose some order on the mess. All I got for my efforts typically was put in charge of databases - something i didn't want to be in charge of. And then there was the time when I worked with a self taught developer who built out an entire ecommerce platform, front and back end, including a jquery-like (but *not jquery :~ :mad:) engine for the front end. Rather than doing JOINs in the database he was doing them in PHP on the webserver. I taught him SQL. Then I quit.
Real programmers use butterflies
honey the codewitch wrote:
Rather than doing JOINs in the database he was doing them in PHP on the webserver
I had a colleague like that once. He was transferring two 100G entries tables (+-50 columns each) to PHP to do joins using for loops. It was killing the server and taking almost a week to process. The boss only noticed when he requested a new, more powerful server (our server was brand new). Boss told me to converted it to SQL and it started taking less than an hour to do the same join ;P That colleague quit the project soon after that.
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How many here normalize their databases?
Bastard Programmer from Hell :suss: "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
I almost always use third normal form to begin with and keep it that way unless there are performance problems.
