Modern languages like Kotlin don't even allow static methods. To me, flexibility (in such cases) == no discipline == laziness. Can’t ensure that each value is the right data type: no way to prevent 1,2,3,banana,5; Can’t use foreign key constraints to link values to a lookup table; no way to enforce referential integrity. Your fine doing lightweight for proof of concept, just don't make things you have to unmake later. Bad Words. In Ender's Game, who fired the Little Doctor? Denormalization can be a query optimization, to be applied when the need actually presents itself. No, it's a horrible idea. Why even save the data for a proof of concept? **, With CSV: Hard to join the values to the lookup table they reference.**. A man’s character may be learned from the adjectives which he habitually uses in conversation. That at least ensures the proper data type, has no problems with distinguishing the delimiter from the actual data and it can be efficiently indexed. https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/3653507#3653507, https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/3653532#3653532, https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/3653497#3653497. +1 just to counter the downvotes. Online word processor for the novelist, blogger, writer needing synonyms. Is there a distinction between “victuals” and “vittles” that exists in writing but not in speech? Vampires as a never-ending source of mechanical energy. https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/53566631#53566631. With CSV: Plus a lot of comma characters. There are some things in there I'm not entirely happy with, one of them is the topic of this question. How to use stringstream to separate comma separated strings [duplicate] Ask Question Asked 8 ... @DmitryGusarov It's a habit and a good practice. Its ridiculousness illustrates the point I'm making, which is that it makes no sense to warn him against something you have no reason to think he needs to be warned about. This rings alarm bells. More here. How to use stringstream to separate comma separated strings [duplicate]. These users are either misguided or stating a religious conviction. It's a defensible choice, but that doesn't make it correct or good. Connect and share knowledge within a single location that is structured and easy to search. Input numbers are specified in a comma-separated list format, so we use the comma symbol in the input separator option. Comma-separated lists are wrong enough that I made this the first chapter in my book: SQL Antipatterns: Avoiding the Pitfalls of Database Programming. Which great mathematicians were also historians of mathematics? Hard to join the values to the lookup table they reference. It doesn't matter in short examples, but. https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/3653541#3653541. For example, look at “Washington, George.” The procedure to split that into two words would be: Calculate the length of the string. You do lose the flexibility of making queries but on the other hand, if you have a library that persists/derpersists the key value pair then it's not a that bad idea. Second answer in the duplicate target also answers this question: Why do you guys always use std:: and full namespaces instead of using namespace? Now, I know that the correct solution would be to create a second table and properly normalize the database. The only reason you should do something like this is that you know how to do it "the right way" but you have come to the conclusion that there is a tangible reason not to do it that way. There's very few "horrible" ideas in sw development - mostly they're just ideas with very limited applicability. By being an xml field, some of the concerns can be addressed. (Some users would dispute the statement in my previous paragraph, saying that "you can never know what requirements will be added in the future". – jrok Oct 14 '19 at 7 ... Why do "beer" and "cherry" have similar words in Spanish and Portuguese? Canât enforce uniqueness: no way to prevent. It is also possible to delete a key:value pair with del. Sometimes it is advantageous to work to the requirements you have before you.). Ubuntu 20.04 best way to make file server? This is short and readable which is great, but is this the fastest way to do it in c++? With XML: tags are used instead of commas, In short, using XML gets around some of the issues with delimited list AND can be converted to a delimited list as needed. I chose to save them in a comma separated list of values stored in one column of the database table. I'm also asking because I'm thinking about cleaning up the program and make it more maintainable. There are times when you need to employ denormalization, but as @OMG Ponies mentions, these are exception cases. in that case, why bothering database?, saving in a file will do. Yes, it was intended to be ridiculous. An ARRAY (of any datatype) can fix the exception, just check PostgreSQL: @CraigRinger, yes, it's a type of denormalization. Find the position of the comma (this shows where one word ends and the other begins). With CSV: Storing integers as strings takes about twice as much space as storing binary integers. The main operations on a dictionary are storing a value with some key and extracting the value given the key. Why are elementwise additions much faster in separate loops than in a combined loop? Whenever you want to block certain words that you feel are inappropriate for your comments section (unwanted words, profane words, or spammy words), just add them after the blacklist words list, exactly as our list format, one word/phrase with comma-separated, so you can review before it is shown in the comments section. Non-plastic cutting board that can be cleaned in a dishwasher. I think I found an error in an electronics book. Opt-in alpha test for a new Stacks editor, Visual design changes to the review queues. Agreed with @thavan. Podcast 312: We’re building a web app, got any advice? If you want to find out more about how positive adjectives and words are defined, visit positive words page. Hard to choose a separator that is guaranteed not to appear in the values, how to get a count of specific values from the comma separated list, how to get records that have only the same 2/3/etc specific value from that comma separated list. In general, storing data in this way is suboptimal (e.g. May have to resort to regular expressions, for example in MySQL: Hard to count elements in the list, or do other aggregate queries. You need to separate the data into logical fields/columns/whatever you want to call them before you can manipulate it meaningfully at all. Paul, I agree. Yes, I would say that it really is that bad. Both are correct.) to check checkboxes in a list from driver table in least common scenario without having to go to another table to get them. Words from this list will be removed from file names while parsing for the title. You could also use a SET (I forget the exact syntax). I always hear some people saying that "my design is more flexible than yours" when I confront them about things like not setting up foreign key constraints, or storing lists in a single field. This comes in handy if you some special words like release groups in your file names. Having said this: if the data you are choosing to store this way is data that you will never need to query by, then there may be a case for storing it in the way you have chosen. With CSV: Hard to fetch the list in sorted order. harder to do efficient queries) and may cause maintenance issues if you modify the items in your form. At some point, normalization might become interesting, but with all the data shoved into a single column you're gaining virtually no benefit from using a database at all. With CSV: Can't enforce uniqueness: no way to prevent 1,2,3,3,3,5. How do I iterate over the words of a string? ah, so it sounds like the problem caused by c++ ability to have a method outside of a class. So the stringstream::>> operator can separate strings by space but not by comma. Comma definition, the sign (,), a mark of punctuation used for indicating a division in a sentence, as in setting off a word, phrase, or clause, especially when such a division is accompanied by a slight pause or is to be noted in order to give order to the sequential elements of the sentence. Or leave it as it is and learn the painful lesson of a SQL injection attack. It doesn't matter in short examples, but using namespace std; is bad in real code. In Kotlin, you can declare functions inside. With CSV: Can't ensure that each value is the right data type: no way to prevent 1,2,3,banana,5, With XML: values in a tag can be forced to be the correct type. Why is “using namespace std;” considered bad practice? Is there anyway to modify the above code so that I can get the following result? With CSV: Can't use foreign key constraints to link values to a lookup table; no way to enforce referential integrity. @Paul: And maybe the same attitude will lead to him being hit by a bus when he fails to look both ways before crossing the street, but you haven't warned him about that. SQL Antipatterns: Avoiding the Pitfalls of Database Programming, postgresql.org/docs/current/static/arrays.html, querying an XML list in sql server using Xquery, Canât ensure that each value is the right data type: no way to prevent. How can I get self-confidence when writing? I am revising the design now that I have learnt NHibernate but back then I needed the flexibity to design the form in ASP.NET and use the textbox ids as key in the key/value pair. Telling someone who has maintained the app for 4 years about maintenance concerns is a bit presumptuous. I'd recommend taking the time to do it properly and view it as an opportunity to learn. In general anything can be defensible if it meets the requirements of your project. Mark Twain TWEET THIS LIST OF POSITIVE ADJECTIVES FROM A TO Z “POSITIVE DESCRIBING WORDS” Notice! If you have a fixed number of boolean fields, you could use a INT(1) NOT NULL (or BIT NOT NULL if it exists) or CHAR (0) (nullable) for each. Hard to search for all entities with a given value in the list; you have to use an inefficient table-scan. The form contains some more fields, this is only one part of the form (which I did not explain well in the question). https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/3653500#3653500. Edit: I had thought you were the poster of this answer, my mistake. It was quicker to implement the easy solution, and I wanted to have a proof-of-concept of that application quickly and without having to spend too much time on it. It's reasonable to warn folks on the limitations, but chastising those who have done it and lived through it strikes me as a holier-than-thou attitude I can do without. Are my equations correct here? The csv needs to be comma separated and only the comma itself needs to be quoted with double quotes; Example. Is oxygen really the most abundant element on the surface of the Moon? Transitional words and phrases at the beginnings of sentences move us from one thought, one sentence, to the next. Some more context, this is a small internal application that essentially replaces an Excel file that was stored on a shared folder. Canât delete a value from the list without fetching the whole list. With CSV: Can't delete a value from the list without fetching the whole list. I would probably take the middle ground: make each field in the CSV into a separate column in the database, but not worry much about normalization (at least for now). using stringstream >> operator in if statement, StringStream input with comma delimited string - know columns apriori, Unable to use ostream << overload with stringstream no known conversion for argument 1, Using stringstream inside a loop to extract a number from few strings. Copy the right-hand side of the string from the comma to the end. Is there specific reasoning for this? I know its not recommended, but playing devils advocate: most of these can be taken off if there is a ui that handles uniqueness and data types (otherwise would error or misbehave), ui drops and creates it anyway, there is a driver table where the values come from to make them unique, field like '%P%' can be used, values being P, R, S, T, counting doesn't matter, and sorting doesn't matter. (Yes, I purposely used a comma after in this sentence three paragraphs back and omitted it in the previous paragraph. Copy the left-hand side of the string up until the comma. In addition to violating First Normal Form because of the repeating group of values stored in a single column, comma-separated lists have a lot of other more practical problems:. But as I said I used if for a specific purpose, and that is for a data entry operation where you have many kinds of forms. I think I had far more reason that your warning about buses. Yes, it is that bad. Depending on ui, values can be split[] e.g. Cure writer’s block with built-in thesaurus, dictionary, keyword generator, and more. site design / logo © 2021 Stack Exchange Inc; user contributions licensed under cc by-sa. Canât use foreign key constraints to link values to a lookup table; no way to enforce referential integrity. What was the earliest system to explicitly support threading based on shared memory? How did Woz write the Apple 1 BASIC before building the computer? With CSV: Hard to search for all entities with a given value in the list; you have to use an inefficient table-scan. What you're calling laziness and lack of SQL knowledge is the stuff that neophytes are made of. Once you have the proof complete, then add a database correctly. @Hammerite - your extrapolation to buses is ridiculous. 2021 Stack Exchange, Inc. user contributions under cc by-sa. How did my 4 Tesla shares turn into 12 shares? I thought the saved time and simpler code was worth it in my situation, is this a defensible design choice, or should I have normalized it from the start? You might be misreading cultural styles. querying an XML list in sql server using Xquery. With CSV: Hard to count elements in the list, or do other aggregate queries. Why are video calls so tiring? Can't store a list longer than what fits in the string column. Prove that in a *nonlinear* circuit, adding resistor between equipotential terminals draws no current. In addition to violating First Normal Form because of the repeating group of values stored in a single column, comma-separated lists have a lot of other more practical problems: To solve these problems, you have to write tons of application code, reinventing functionality that the RDBMS already provides much more efficiently. A second criticism is that putting raw input results directly into a database, without any validation or binding at all, leaves you open to SQL injection attacks. You've managed to get away with it, but the cost of your few minutes of development time has cost you lousy query performance, flexibility, and maintainability of your code. Transitional Words and Phrases. Any non-relational âoptimizationâ benefits one type of query at the expense of other uses of the data, so be sure you know which of your queries need to be treated so specially that they deserve denormalization. When used carefully, denormalization can be just the right thing to do for a certain query you are trying to optimize, but it must be done with full understanding that it harms other queries. C++ parsing an input file line into an array of objects, Issue reading multiple lines from .txt file in C++. If those other queries aren't important to your application, then the pain is less. Many are conjunctive adverbs. How do you set, clear, and toggle a single bit? Is storing a delimited list in a database column really that bad? rev 2021.2.12.38571, Sorry, we no longer support Internet Explorer, Stack Overflow works best with JavaScript enabled, Where developers & technologists share private knowledge with coworkers, Programming & related technical career opportunities, Recruit tech talent & build your employer brand, Reach developers & technologists worldwide. These are all symptoms of denormalized data, and highlight why you should always model for normalized data. https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/17620576#17620576, https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/3653657#3653657, https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/3653520#3653520. Yes, I see. @DmitryGusarov It's a habit and a good practice. Join Stack Overflow to learn, share knowledge, and build your career. Well I've been using a key/value pair tab separated list in a NTEXT column in SQL Server for more than 4 years now and it works. https://stackoverflow.com/questions/3653462/is-storing-a-delimited-list-in-a-database-column-really-that-bad/3653574#3653574. In Postgres, an array column should be preferred over a comma separated list. This example sorts 15 rational numbers in decreasing order. Easiest way to convert int to string in C++. How to create a spiral using Golden Triangles. SQL injection and database normalisation are orthogonal topics, and your digression on injection is irrelevant to the question. I don't see anything in this question that suggests he is vulnerable to SQL injection. FANBOYS is an acronym made from the first letter of each coordinator— For, And, Nor, But, Or, Yet, So.. clause – (1) a finite clause—one or more noun phrases together with a predicator (a verb) that combine to express a complete thought (a stand-alone sentence); (2) a nonfinite clause—a verb or a verb with complements that express limited meaning (not a stand-alone sentence). I needed a multi-value column, it could be implemented as an xml field, It could be converted to a comma delimited as necessary. But is it a good practice to have a method outside of a class? Why didn't Escobar's hippos introduced in a single event die out due to inbreeding. Perhaps you could have found a middle ground and used an integer representing a set of bit flags instead? Where is the line at which the producer of a product cannot be blamed for the stupidity of the user of that product? For the sorted list, we put the ">" symbol as the output separator to visualize the descending order of sorted numbers. Placing a comma-separated list of key:value pairs within the braces adds initial key:value pairs to the dictionary; this is also the way dictionaries are written on output. How do you clear a stringstream variable? With XML: storage is even worse than a csv. My view is that if you don't like using relational databases then look for an alternative that suits you better, there are lots of interesting "NOSQL" projects out there with some really advanced features. I just always find it as a very noisy and had-to-read syntax. And probably this is why it never lead to problem in C# / Java. Imagine a web form with a set of check boxes (any or all of them can be selected).
Logitech G560 Reddit,
Tom Delonge Squier,
Shinobi Life 2 Custom Eye Id,
Nch Staff Email Login,
Gourmet Jelly Beans Costco,
Buddhism Letting Go Quotes,