Questions regarding efficient storing and representing data within a software application.

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1answer
100 views

Multitenancy and nested set trees

The application I work on utilizes nested sets1 to represent tree structures within our database. We need to expand a particular area of access control to support multiple clients who should not be ...
0
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2answers
31 views

Making sure loaden (non default) config is valid

I'm writing a device Software in which the device must handle much data. Therefore it has a database, either on NV-Ram (Non-volatile memory) or a SD-Card. Due there's a DB which I can use, I also use ...
1
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4answers
152 views

What do polynomial algorithms entail?

From here, I know it is that an algorithm that... ...is said to be solvable in polynomial time if the number of steps required to complete the algorithm for a given input is O(n^k) for some ...
0
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1answer
133 views

Application with really dynamic data structure [closed]

Well, I'm on the verge of this project that really puzzled me. The situation is, in our office, we have a department that collect data about the corporate performance indicators from all across the ...
5
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1answer
2k views

Building a Graph Editor - How to create a data driven graph

I am developing a graph-editor that uses drag and drop to build hierarchical graphs (containing nodes and links). Each node in the graph should be linked to a table in our database (SQL Server). I did ...
1
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2answers
106 views

Structuring data to represent a tree with squirrels

What I want to represent Let's assume I have several schemas of the following kind: It is a tree on which positions of squirrels are represented by a blue dot. The number of bifurcations differ ...
0
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1answer
1k views

How to remove a middle element from queue?

I had a question, about how to remove an element from middle of the queue , without disturbing the order of other elements. E.g. Queue before operation:- <| a b c d e |< Queue after ...
4
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2answers
104 views

Is it a good idea to have a database row that represents an unknown value within a system [closed]

We have two systems, System A imports a list of sports events from system B, it only wants to import the events we will be providing live data for, the filter used to hide events that we are not ...
-1
votes
2answers
256 views

Efficiently save big data structures [closed]

I need to save big data structure (Tree with specific nodes) into file efficiently. Data is always changing, so I need to rewrite whole data structure very often, so simple serialization is not good ...
2
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2answers
471 views

Traversing an AST using Visitors

I'm writing a compiler for a C-like language, and I'm looking for an elegant way to traverse my abstract syntax tree. I'm trying to implement the Visitor pattern, although I'm not convinced that I'm ...
-1
votes
1answer
116 views

What are some hashmaps we can easily implement? [duplicate]

At many places, I read that we can use HashMap here for O(1) search. Actually, I want to ask how I can implement easy hashmaps which can satisfy this property. Can anyone tell few hashmaps including ...
2
votes
1answer
190 views

How to make max-heap stable with counter and account for counter overflow?

Generally I need size-efficient data structure similar to std::priority_queue but stable (preserving order of insertion). By adding just 4 bytes to the object I could have 1 byte serving as priority ...
2
votes
1answer
207 views

How to organize points on a sphere in bins and navigate between bins?

I'm having trouble coming up with a suitable way to navigate through a set of star coordinates in the Equatorial Coordinate System. My goal is to display those which are within a given range of ...
2
votes
1answer
272 views

Graph data structures and journal format for mini-IDE

Background: I am writing a small/partial IDE. Code is internally converted/parsed into a graph data structure (for fast navigation, syntax-check etc). Functionality to undo/redo (also between ...
1
vote
1answer
154 views

Where to put data for tree structure which every node requires?

I have a quad-tree structure where each node has some of its own data, but there is also data which applies to the tree as a whole. I'll explain my current solution and I would appreciate feedback on ...
2
votes
2answers
399 views

How to present a stable data model in a public API that allows internal data structures to be changed without breaking the public view of the data?

I am in the process of developing an application that allows users to write C# scripts. These scripts allow users to call selected methods and to access and manipulate data in a document. This works ...
2
votes
1answer
251 views

Data structure well suited for duplicate entries

I'm in the process of getting to know (modern) filesystems. As part of it, I came across log structured filesystems that also handle allocations in a log structured way. I wonder how they handle ...
4
votes
1answer
424 views

Using macros to implement a generic vector (dynamic array) in C. Is this a good idea?

So far I have only done personal projects at home. I hope to get involved in some open source project some time next year. The languages I that have been using the most are C and C++. I have used both ...
2
votes
2answers
198 views

Is embedding data in a executable considered a good practice?

Embedding data (such as images) in a executable seems to have a few advantages, like easier distribution of the executable and easier compatibility with different OSes. But, is it a good practice? ...
4
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1answer
277 views

Why define struct in variable?

Consider the following program: Many people when they want to use a struct, they create a new variable as: struct structureName variableName While it works when you just define it as: ...
8
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2answers
1k views

Ideal data structure/techniques for storing generic scheduler data in C#

I am trying to implement a generic scheduler object in C# 4 which will output a table in HTML. Basic aim is to show some object along with various attributes, and whether it was doing something in a ...
10
votes
8answers
5k views

Data structure for accessing units of measure

TL;DR - I'm trying to design an optimal data structure to define units within a unit of measure. A Unit of measure is essentially a value (or quantity) associated with a unit. SI Units have seven ...
8
votes
3answers
1k views

What is the Bible of Hashing?

Is there a Cormen-like reference on Hashes and Hashing? This particular structure has seen little attention in my CS education for some reason but I'd like to learn more as they seem to be everywhere. ...
5
votes
2answers
327 views

Why Do B+ Trees Have a Minimum Occupancy of 50%?

As far as I can tell, the basic operations (add, delete, search) on a B+ Tree would function the same if minimum occupancy was 1, or 1/3, or any other function on node size. All the sources available ...
0
votes
1answer
421 views

calculating the average of a value over a month [closed]

I am working on a project right now that is having me calculate monthly interest on a bank account. The way the interest is supposed to be calculated is as follows: Use the daily average to calculate ...
0
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1answer
65 views

Efficient storing and multidirectional lookup of hierachical data

I make a game and among others I have nations, provinces, tiles and armies. Each army belongs to exactly one tile, each tile belongs to exactly one province, each province to exactly one nation. I ...
3
votes
1answer
471 views

Is using MultiMaps code smell? If so what alternative data structures fit my needs?

I'm trying to model nWoD characters for a roleplaying game in a character builder program. The crux is I want to support saving too and loading from yaml documents. One aspect of the character's is ...
2
votes
2answers
411 views

Most efficient way to store this collection of moduli and remainders?

I have a huge collection of different moduli and associated with each modulus a fairly large list of remainders. I want to store these values so that I can efficiently determine whether an integer is ...
0
votes
1answer
97 views

Handling the process of large-scale lists [closed]

What are the efficient ways to process huge lists (+10 millions), and things to consider while manipulating huge lists. First question, when should I use recursion, and when I shouldn't. In both ...
0
votes
1answer
110 views

Method ordering

This is the type of question that one would probably get in an exam, but now it happens to be in the real word. :-) I would appreciate some advice regarding the datastructure/algorithm that can be ...
0
votes
1answer
433 views

Find possible variations of one item out of multiple baskets.

I have three baskets of balls and each of them has 10 balls which have the following numbers: Basket 1: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 Basket 2: 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 ...
1
vote
1answer
473 views

What is a good way to store geographical data for distance calculations

What would be the best way to store data in a database for geographical calculations? Say I have an ItemsForSale table paired to a Users table which holds their geo location. I know I can use latitude ...
1
vote
3answers
2k views

Database design: 4 types of users but have different functionality , separate or one table?

I have 4 types of users: Admins , normal user , company , service provider admins and normal user share some attributes (id .first name ,last name ,phone ,mail) company and service provider share ...
3
votes
2answers
503 views

Process to generate hierarchical structure based on relational data?

I have a csv of employee ids, names, and a reference column with the id of their direct manager, say something like this emp_id, emp_name, mgr_id 1,The Boss,, 2,Manager Joe,1 3,Manager Sally,1 ...
1
vote
1answer
124 views

Best approach to a defined datastructure

I have a plain text file with some data that I can't change, so I have to create a datastructure to use in reading the file and with that datastructure do some thousands of interactions. The file ...
3
votes
0answers
213 views

Lightweight data modeling vs traditional classes [closed]

I've heard a lot of talk about using lightweight data modeling as of late. Especially in relation to the Clojure programming language. What is it and how it differs from traditional classes regarding ...
2
votes
1answer
78 views

BloomFilter in ruby should have k hash functions

I am reading the Bloom Filter implementation written in ruby. It should have k hash functions, but it looks like the same hash function is being used with different seed values. Is this a common way ...
0
votes
1answer
54 views

What would be the return type of a cartesian product of a multiset

I am writing a Multiset in Ruby. The Union, Intersection operations where simple and return a MultiSet. But, I am not sure what the return type of the cartesian product should be, should I return an ...
1
vote
3answers
277 views

Pattern / methodology for representing large database records as objects

A bit of background information: We have an old database application written in Access that lets users monitor their workload, and the code is... 'procedural' might be too kind. The vast majority of ...
2
votes
3answers
1k views

Programming language with pattern matching in trees [closed]

I'd like to prototype a computer algebra system. An equation would be represented by a tree and rules would be defined - similarly to mathematical axioms - by specifying a pattern (in the tree) and a ...
4
votes
2answers
224 views

Decimal vs. Integer; Given a fixed range of values, which is preferable for accurate computation?

After getting into a "heated discussion" with someone, I figured I'd ask this question for the sake of posterity. I'm willing to be corrected if my assumption is incorrect but I'd like to hear a ...
9
votes
3answers
968 views

Clean Code and Hybrid Objects and Feature Envy

So I recently made some major refactorings to my code. One of the main things I tried to do was split out my classes into data objects and worker objects. This was inspired, among other things, by ...
1
vote
1answer
282 views

What was the influence of Chris Okasaki's data structures on Scala? [closed]

I heard a friend say: The first real use of Chris Okasaki's book was in Clojure's data structures I heard another friend say: No, they influenced the design of Scala in quite a subtle way. ...
0
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3answers
168 views

At what level of abstraction are data structured created?

I am learning about Linked List and Arrays in my data structures class. We are make them in Java. Are actual data structures designed in Java/C? Or are they made in lower level languages like ...
3
votes
3answers
474 views

Separating Code into Smaller Files in C

I am in the process of cleaning up my code and making it easier to maintain. I am doing this by turning my 5000+ line file into separate smaller files. I have successfully created separate source and ...
1
vote
3answers
266 views

Is there a programming pattern, design pattern, or naming convention for moving data between related schemas? [closed]

I'm working on a web application that is publicly accessible. (Really) Long story short, we have two sets of tables in the database with relatively the same names and relatively the same data. The ...
6
votes
3answers
1k views

Is a tree with nodes that have reference to parent still a tree?

If we make reference to the parent for each node in a tree, do we still have a tree (by definition) anymore? Wikipedia definition is: In computer science, a tree is a widely used abstract data ...
7
votes
2answers
4k views

Amortized Analysis? (Worst-case Performance Guarantees)

What is Amortized Analysis? And how can it help me achieve worst-case performance guarantees in my programs? I was reading that the following techniques can help the programmer achieve Worst-case ...
1
vote
4answers
599 views

How to work around Java's lack of pointers to pointers when working with linked data structures? [closed]

I've learned from a textbook how to implement binary search trees recursively in Java, and am working on implementing them nonrecursively. I've found a simple and elegant way to implement an insert ...
0
votes
2answers
894 views

Exercise 3.6: Skiena Algorithm Design Manual

I am preparing for interview and try to solve the exercise problems of the book. 3-6. [5] Describe how to modify any balanced tree data structure such that search, insert, delete, minimum, and ...