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Questions tagged [relational]

526 questions
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Data Structure To Store Arbitrary Database Tables

I'd like to design a JVM data structure (Java/Scala) that can be used to represent and store the contents of arbitrary relational database tables. The data structure should be fast (not too gc-intensive, cache-friendly) and memory efficient, so…
Seun Osewa
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use relational operators in switch

Is there a way to use relational operators (<,<=,>,>=) in a switch statement? int score = 95; switch(score) { case (score >= 90): // do stuff } the above example (obviously) doesn't work
qsi
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What relational database innovations have there been in the last 10 years

The SQL implementation of relational databases has been around in their current form for something like 25 years (since System R and Ingres). Even the main (loosely adhered to) standard is ANSI-92 (although there were later updates) is a good 15…
Simon Munro
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Relational camp and "real-world" database development

More than decade passed since first publication of Date's and Darwen's "The Third Manifesto" in 1995. What is the place of relational school of thought in today's database world? Is there any evidence that Manifesto's ideas changed mainstream…
Constantin
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How to retrieve "dynamic" attributes stored in multiple rows as normal records?

I have a system built on a relational MySQL database that allows people to store details of "leads". In addition, people can create their own columns under which to store data and then when adding new accounts can add data under them. The table…
Raiden616
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Designing a relational database and having a looming feeling of doom

I'm part of a four-man team at a growing company of over 200 users. It's time for a massive refactoring of our proprietary software, and we're very excited to build an ideal system that we know can withstand growth for at least 5+ years. We're using…
Seth Goodwin
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Get Common Rows Within The Same Table

I've had a bit of a search, but didn't find anything quite like what I'm trying to achieve. Basically, I'm trying to find a similarity between two users' voting habits. I have a table storing each individual vote made, which stores: voteID itemID …
James B
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Good Fast Way to Let Users Visualize and Explore Relational Data?

I'm looking for either a web-based or Windows-based way to point to a relational data source using automated schema exploration (or, even better, a reflection-based approach that would work on any IQueryable in-memory data source) and allow easy…
blaster
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How to represent "not exists" in relational algebra?

How do I represent the SQL "not exists" clause in relational algebra?
sudh
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Relational attribute in Yii2 form

I am trying to get to figure out the proper way of handling a form receiving relational data in Yii2. I haven't been able to find any good examples of this. I have 2 models Sets and SetsIntensity, every Set may have one SetsIntensity associated with…
Ric
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DELETE a record in relational position in MySQL?

I am trying to clean up records stored in a MySQL table. If a row contains %X%, I need to delete that row and the row immediately below it, regardless of content. E.g. (sorry if the table is insulting anyone's intelligence): | 1 | leave alone | 2…
user2178465
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OWL to relational transformation tools

I am starting to work with OWL using Protégé. It is all very intuitive for someone with a background on ontologies. With the onotology specified I would need to implement it as a relational schema in a DBMS. I have so far found references to two…
Luís de Sousa
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How to design a media table with references to multiple (at least 4) tables?

I am designing a database for my cookbooks. I have created multiple tables in my design: books, authors, recipes, ingredients and for all these items I want to link media (images or video) to items in all these tables. I was thinking of a design…
Matthijs
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Relational Databases: Current Data vs. Historical Data, best Practice

Let's take a relational database, e.g. MySQL. To keep it simple, i will concentrate on the important things: Having a table that contains orders, with fields like order_id (primary key) order_date and a foreign key fk_supplier, which references a…
whocares81
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Database schema-related problem

I have a kind of theoretical question about databases. To make it more concrete I have thought up an example case. Suppose I have a store with products. I have lots of different products. Not every product has the same applicable properties. For…
Bram Jetten
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