This tag is for general database questions; if you question is specific to SQL use that tag instead.

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1
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1answer
73 views

Database integration of Rails and Laravel apps

I have some very small apps on a VPS running ruby on rails and a co-worker also have some of his own apps running on laravel at another VPS. So far we dont needed to share any data among the apps, but ...
0
votes
1answer
520 views

Like structure table with Laravel and showing the most popular content at top

I am using Laravel to creating a website, my users can post questions and other users can write their comments under the post, each comment have Up vote and Down vote, and users can voting for ...
13
votes
6answers
40k views

what do database programmers do?

Every time I read about Oracle programmers etc, I get confused. I don't know what exactly they do. From my understanding, application programmers need to develop the core functionality. The libraries ...
1
vote
2answers
276 views

Multiple instance of the same class?

I have a class named "Category" to handle all the operations and data about my categories. Now, my class is created however I need to find a way to build an object for each of the categories in my ...
-2
votes
1answer
37 views

How do I draw an Entity Relationship Diagram in a diagram with different level?

I'm am beginner and doing internship at a company. He asked me to develop a program to supervise their staff working progress. He said the system should have different level of users and the system ...
2
votes
1answer
68 views

Executing queries against multiple separate database instances

Premise I have a number of database servers (different DBMS instances, installations in different physical locations), each of them contains data and uses the same schema. Most of the data is ...
2
votes
0answers
62 views

Logging Database Changes

What is the proper way of storing a changelog, similar to git, for data in a database. Currently, I have it set up so that every line in a table is given a unique string id that is used to ...
-1
votes
0answers
22 views

Using Neo4j in ASP.NET application when collaborating with SQL Server?

I'm going to develop an online video platform with the feature of social network using ASP.NET. In the requirements, users can not only upload, watch and download videos, but also make friend with ...
1
vote
0answers
38 views

Saving tabular, spreadsheet-like data in a relational database?

I'm hoping this question isn't too broad or too prone to opinionated answers, since I could really use some pointers. I'm trying to come up with a way to persist tabular, spreadsheet-like1, data in a ...
-4
votes
0answers
22 views

When should I use adjacency list model and nested sets?

I'm going to create an online store, and I'm misunderstanding with my database. 1/ when should I use adjacency list model? 2/ when should I use nested sets? Nested Sets algorithm is very new for me! ...
4
votes
1answer
246 views

Reuse already fetched data for request

I have action that fetches user model from db to check access. Then I have method that in some cases requires same model. function checkAccess(req, res, next) { var data = ...
2
votes
3answers
80 views

How can one think of a relational schema in terms of storing it in a NoSQL database?

Recently I've been wanting to experiment with NoSQL databases, especially document store ones. After reading, I still don't understand how one might model information that is contained in a relational ...
55
votes
7answers
5k views

Why does the relational model for a database matter?

I am approaching a project where I'll be having to implement a database with my boss; we're a very small start up so the work environment is deeply personal. He had given me one of the company ...
1
vote
1answer
82 views

What is the correct reusable architecture using Entity Framework for common database tables and services?

Context I have a line of business application "MyApp" in C# using EF. Layers are separated as MyResusableLib.DataAccess // Class Lib: EF based utils, extension methods, MyApp.DataAccess // Class ...
2
votes
1answer
40 views

Efficient saving of long strings with recurring substrings

following problem: I need to save a lot of xml strings of variable length and structure. As it is with xml, a lot of substrings are the same (some elements, attribute and value combination). Often the ...
23
votes
2answers
13k views

Data Synchronization in mobile apps - multiple devices, multiple users

I'm looking into building my first mobile app. One of the core features of the application is that multiple devices/users will have access to the same data -- and all of them will have CRUD rights. I ...
4
votes
3answers
2k views

Separation of retrieving data and business objects between DAL and BLL Layers

I did some research before posting this question. Among other questions or post, one of those is provided below. I could not get a clear mind how to determine.. Business Objects within a Data Access ...
0
votes
2answers
78 views

JSON or XML or other - most time efficient for largely “read” of structured data

Considering that using a relational DB or other hierarchical or such databases is not an option, looking for the alternative approach using a simple (but very fast, efficient, distributed KV-store). ...
1
vote
1answer
49 views

How to associate similar data with different tables in a database?

My application has users and ads. A user has a unique email. An ad belongs to a user (so, the ads table has a user_id FK, that is simple). Every ad can also have multiple emails and phone numbers ...
16
votes
6answers
40k views

How to quickly search through a very large list of strings / records on a database

I have the following problem: I have a database containing more than 2 million records. Each record has a string field X and I want to display a list of records for which field X contains a certain ...
2
votes
1answer
209 views

How is one or more aggregate function implemented in most SQL engines?

In the book Database Fundamentals, Silberschatz. It is explained that aggregate functions can be calculated on the march. This make sense. What it means is that for calculating the maximun, average ...
1
vote
1answer
42 views

User account model with two or three possible profile

My application will have at least two types of users: clients and companies, these are the types of profiles. Because each type of profile requires different additional information, it will be ...
0
votes
0answers
28 views

Develop an API within ESB to access a database

I am working with a service provider where I need to get data from their service. The service provider wants to give me access to their database to get the data I need. My question is should I ...
4
votes
3answers
1k views

Let applications share a database or keep them in sync with web services?

We have decided to build separate applications for user authentication and user management. The reason is that the the former is a "this just needs to always work, and do so instantly" style service, ...
0
votes
0answers
12 views

Regional test-of-concept environment, whose database must be merged back to the main server afterwards

My client wishes to launch a specific version of the Rails platform I am developing that will be restricted to a particular group of users (some sort of test-of-concept). I will have another server ...
2
votes
0answers
68 views

Maximising data processing speed: in-memory or write to db first?

Currently working on a system which allows users to upload data files, which we then "clean" (i.e. process in various ways). Speed of processing and return to the user is an important consideration, ...
1
vote
1answer
47 views

Implement pagination which memorizes where we left off?

Let's pick a relation database table (say an audit table) with high write rate. We can display 100 records at a time. But as a user don't want to see some the records on page 1 on page 2 when a couple ...
5
votes
6answers
176 views

Should I add a “boolean meaning” to another column?

Is it a good/bad practice to add a "boolean meaning" to other fields? For instance, let's say I'm modeling events, that might be recurring or not. I can have: A boolean column that holds if the ...
-1
votes
1answer
51 views

Any Non-Singleton PHP PDO Db Connection Examples? [closed]

Are there any good examples of non-Singleton PHP PDO Dbfactory or connection classes people can point me in the direction, or perhaps even briefly illustrate. I am interested in learning both support ...
-1
votes
1answer
56 views

How costly is DB data transfer as compared to data storage?

I've seen a number of answers (1, 2, 3) where they state that storage is cheap. So when designing a DB structure, it shouldn't be a main concern, or at least it doesn't rank very high in the list of ...
1
vote
1answer
90 views

Django Migrations: Binds data to code?

If you have custom code for models (custom validators and custom fields are examples), Django Migrations will import them directly into the migration files. An example: file web/models.py def ...
0
votes
1answer
62 views

Datagrids vs Databases - what are the differences?

There are some datagrids I had quick look into: Angular UI Grid ag-Grid, one more link Kendo UI Grid Also, previously I had a very small experience with MySQL. What are the differences between ...
1
vote
1answer
111 views

Getting data from a database with the MVC model

I am creating an application which will have a very large database to draw it's information from (a student registration system to be exact). The database is created with Microsoft SQL Server if that ...
1
vote
1answer
256 views

Making API calls with celery

I'm designing a system for a client where the requirements are: they upload a JSON file (one object/line) make a call to an API with the JSON object as the payload record the state (success/failure) ...
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votes
0answers
91 views

How to insert large text into a DB with PHP? [migrated]

I have a function that generates a random text with about 8,000 characters. This text is generated at the time of first access the page, based on some parameters. I would like this text to be ...
0
votes
1answer
39 views

Keeping track of data deleted upstream

I'm building an application that queries several APIs and duplicates some of the data in a downstream, centralized database to make it easier to perform some processing on it. My application will only ...
4
votes
3answers
57 views

Getting the same data in multiple ways

Say I want to get the same data from an SQL database, but want to have multiple ways of getting that data. For example, say I want to be able to search a database for users based on username, real ...
1
vote
3answers
71 views

Are crow feet notation and uml notation same?

Does crow feet lies under the sub category of the UML notation or it is a whole other approaches. As far i have seen only difference between two of them is that crow feet uses crow symbol ...
0
votes
3answers
70 views

Should an audit user column be nullable?

Consider following table structure, for the backend of a website: [Article] ArticleId Text TotalViews AuditModifiedOn AuditModifiedByUserId [User] UserId An anonymous/not authenticated user visits ...
1
vote
1answer
49 views

How to store data from firebase to analyze at some later date [closed]

I am currently using Firebase with my iOS app. I use it to authenticate users and then allow user interactivity during the life of the app session. I would like to be able to save a snapshot of my ...
2
votes
1answer
55 views

How to optimize a bloated entity that causes a huge query

I have an application that exposes a series of Web services. One of my entities has a bunch of one-to-many and many-to-many relations to other entities. My transactionality level is at DAO, and I'd ...
1
vote
3answers
45 views

Archiving data by semester

The problem is similar to this question, but not a duplicate. What I'm looking for is a better solution than my current one. I'm building a web application for a department in my university, and due ...
0
votes
1answer
71 views

How to do an “Automatic DB monitor” and notify the client

Until now I didn't find anything good about monitoring a DB's specific table (or related tables) specific values changed. I want to know: Since most of DB's don't support monitoring changes for ...
-1
votes
1answer
21 views

Defining a DB schema and having existing schema conform to it?

I see a lot of DB migration tools that have up/down functions that deploy/revert DB schema changes. I have never seen a migration tool where you simply define the schema and it modifies your current ...
-2
votes
0answers
84 views

Database structure for an Android chat application

I have a structuring or rather designing problem. I am developing an Android chat application and I need to know if anyone has an idea on how the database should be structured to allow group and ...
2
votes
1answer
157 views

Elasticsearch and relational database combination

Imagine I have a marketplace application - where users can search for products (we concentrate on clothes). Every product has an ID, name (text), description (text), price (numeric), size (numeric), ...
0
votes
1answer
39 views

Licensing and copyright terms for data from Wikipedia

I have an idea for a client-server software project which involves using information from Wikipedia, but I am not sure about what the conditions for using it in regards of licensing and copyrights ...
42
votes
6answers
2k views

Business logic: Database vs code [duplicate]

I'm a student of systems engineering, and all my teachers and friends (that actually work in the area) say that it is better to have as much logic as possible implemented in the database (queries, ...
3
votes
1answer
114 views

Is it good practice to access database in mapping between object

Situation I receive message from a 3rd party, and these messages are use to create or update database information. Message and data to be updated can be de-serialize in object form, but are not ...
-3
votes
1answer
114 views

C# Share Datatable in Multi-threading

I am beginner in Multi-threading in C# & confuse in current task. My task is to read datatable and display datatable in C# console application using multi threading. I have three threads and one ...