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
80 views

Good way to handle the notification counter like Facebook does

I want to build a similar notification mechanism that Facebook handles. I actually store the user's notification in an SQL table (actually it's a graph database but everybody master RDBMS terms). ...
0
votes
1answer
36 views

Multiple intranet/internet systems partially working on same data - database strategy

We are starting rewritting our apps (Internet portal, millions of unique users and few CRM/ERP systems, few hundred users) and we have a huge decision to make now. We are going to write them mostly ...
0
votes
4answers
127 views

MySQL Database design - Opinions

Im working on a web Application for our bussiness with my brother. Our application its pretty simple, will be develop with php and mysql. Clients and providers ABMs Articles Inventory (we do not ...
0
votes
1answer
108 views

Keep user and user profile in different tables?

I have seen in a couple of projects that developers prefer to keep essential user info in one table (email/login, password hash, screen name) and rest of the non essential user profile in another ...
2
votes
1answer
96 views

How to model a one-mandatory-of-many relationship

I have following class model that I'm quite happy with: A Whole has a special mandatory Part. Furthermore it has a collection of parts, that contains at least the mandatory part, but may contain ...
1
vote
2answers
243 views

How to update a row in database without ID?

I've got a table with the following structure : Col1 | Col2 | Col3 A | B | C A | C | B E | D | C The primary key is (Col1,Col2,Col3). I get the data in another project and ...
3
votes
2answers
113 views

How are composite tables generally handled when there is no ORM tool available?

I am developing a Windows Runtime Component (C#) to be used in an HTML/JS frontend for a Windows Store App. Now, one of the requests is to have a database on the local system to store metadata about ...
0
votes
1answer
273 views

PHP class data implementation

I'm studying OOP PHP and have watched two tutorials that implement user login\registration system as an example. But implementation varies. Which way will be more correct one to work with data such as ...
0
votes
2answers
79 views

Best way to port Pascal persistence method to C# [on hold]

My new jobs is to port a Delphi application to C#. The Delphi application was originally developed as a proof of concept and after it entered production the company wanted it ported. I'm required to ...
1
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2answers
87 views

Databases and the single responsibility principle

Can the single responsibility principle be applied to databases? relational databases I mean. I'm asking this because a typical database will have several tables and we may find something like that ...
6
votes
2answers
227 views

How does datomic handle “corrections”?

tl;dr Rich Hickey describes datomic as a system which implicitly deals with timestamps associated with data storage from my experience, data is often imperfectly stored in systems, and on many ...
0
votes
1answer
68 views

Locking database records

What I have right now: A table with lot of records. About 200 users can select a record according to some rules based on the data in each record. There is a high chance that 2 or more users will ...
1
vote
1answer
224 views

Organising data access for dependency injection

In our company we have a relatively long history of database backed applications, but have only just begun experimenting with dependency injection. I am looking for advice about how to convert our ...
3
votes
1answer
155 views

implementing dynamic query handler on historical data

EDIT : Refined question to focus on the core issue Context: I have historical data about property (house) sales collected from various sources in a centralized/cloud data source (assume info ...
1
vote
3answers
92 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, ...
-2
votes
1answer
67 views

Should I pass the database access class around or query the database and pass the results? [closed]

Bog standard application, but I'm new to databases. I have a wrapper class around the database, and I can see what looks like two sensible ways to structure procedures viewing the data from the ...
0
votes
2answers
144 views

SOA, Java EE and data organization

At the company I work for, we're currently splitting up our monolith solution into a number of small services (SOA). The purpose of this is to make the developers working on each chunk of code ...
12
votes
7answers
1k views

Why shouldn't you develop on production database? [duplicate]

I need help with organizing my arguments for why it's MADNESS to develop against production data. Backstory: I started working here six months ago and I noticed we're developing directly against ...
2
votes
2answers
87 views

Should I be using a composite key for this table?

My database is going to store words, so the Word table is the most important. The Rhyme table lists which words a particular word perfectly rhymes with. It consists of three fields: RhymeID - primary ...
0
votes
1answer
43 views

Should I persist notification before or after publishing it through Redis pub/sub?

I'm implementing a mechanism to notify a group of users about newly inserted blog comments. The architecture uses the Redis Pub/Sub mechanism. By definition, the pub/sub mechanism aims to propagate ...
0
votes
0answers
37 views

Connection Pooling

As an example, I am using PostgreSQL with an application-layer connection pool, such a a JDBC connection pool. The specific JDBC connection pool is not important. My question is more about the actual ...
3
votes
1answer
90 views

End user query syntax?

I'm making a command line tool that allows end users to query a statically-schemed database; however, I want users to be able to specify boolean matchers in their query (effectively things like "get ...
0
votes
0answers
26 views

How to test for performance or locking issues of sharing a database with another app

I have a typical Spring/Hibernate Tomcat webapp that has a user_info table. I’m trying to create another webapp that will do CRUD actions on the user_info table. I'm considering sharing the same ...
0
votes
0answers
43 views

Save database changes in service layer or controller mvc .net

I have recently been using a service layer to abstract away alot of the business logic of my application. However I've come into an issue where I'm not sure what is best practice on doing the actual ...
11
votes
4answers
302 views

Database design - Store state or compute state every time?

Let's say I have a relational database application and a "user" object and a "message" object. Now I want to show the number of unread messages to this user. What's the best way to archive this? Do I ...
14
votes
2answers
10k views

Creating database connections - Do it once or for each query?

At the moment I create a database connection when my web page is first loaded. I then process the page and run any queries against that conection. Is this the best way to do it or should I be creating ...
0
votes
2answers
146 views

Examples of designing a database that handles point tracking?

I'm attempting to expand my knowledge of how database designs and concepts work. I'm working on a hobby web/mobile app for practice that will challenge me. However, I am running into an issue. What ...
4
votes
5answers
1k views

Structuring database for multi-object “activity” and “following” functionalities

I am working on a web application which operate with different types of objects such as user, profiles, pages etc. All objects have unique object_id. When objects interact it may produce "activity", ...
-2
votes
0answers
44 views

Any composite keys limitations with EF? [migrated]

Some ORM for .NET have limited support for composite keys. Stuff like relations, variant types and LINQ queries may or may not work depending on the case. I've even seen one ORM that doesn't even ...
2
votes
1answer
334 views

Which is the best method for storing data for a Language Dictionary?

I have been working on making a completely offline dictionary using the Wiktionary XML dumps. The dumps themselves are about 10 MB, but when converted into a index using a search engine indexer (I use ...
-1
votes
1answer
64 views

is database the only thing which makes a application/software complex [closed]

i want to know what thing makes a application complex? is it only the database or some other things. what if Facebook has only thousand users then would it be so complex as it is now.
0
votes
2answers
88 views

Guidance on connecting a common database to several instances of the same application [closed]

I'm looking for advice regarding a future development of mine, concerning a application that may be run in several machines that need to use and manipulate the same data. As this sounds somewhat vague ...
3
votes
4answers
362 views

Best practices when creating/modeling databases?

I learned at the University some steps to model a database: Model the problem using the Extended Entity-Relationship Model. Extract the functional dependencies Apply some algorithms to normalize ...
0
votes
0answers
131 views

Extending user registration in Django site that uses both site admin tables and my own module?

I'm writing a Django site that registers a particular type of user and this is done by the resources that come with the framework, the site administration. The issue: I'd like to create a new model ...
0
votes
0answers
22 views

What are the memory-management capabilities of MySQL + JDBC (in light of autonomic computing)?

I'm interested in implementing some kind of autonomic-computing functionality using MySQL. By autonomic-computing I mean roughly some failsafe abilities, whereby the application appears to be at least ...
2
votes
3answers
60 views

Should custom data elements be stored as XML or database entries?

There are a ton of questions like this, but they are mostly very generalized, so I'd like to get some views on my specific usage. General: I'm building a new project on my own in Django. It's focus ...
1
vote
2answers
81 views

How can you predict the time it will take for two processes in two different machines in a cluster to communicate?

I am trying to develop a computing application which needs a lot of memory (>500gb). Buying a single machine for that is overly expensive. I can, though, buy ~100 small instances on Digital Ocean or ...
8
votes
5answers
9k 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 ...
0
votes
0answers
59 views

Appropriate design / technologies to handle dynamic string formatting?

recently I was tasked with implementing a way of adding support for versioning of hardware packet specifications to one of our libraries. First a bit of information about the project. We have a ...
1
vote
1answer
47 views

storing map template in database

I am working on an application that displays choropleth maps. These maps are of all different types, some display state by county, country by state/province, or world by country. How should I ...
5
votes
4answers
5k views

What is the best way to work with large databases in Java depending on context?

We are trying to figure out the best practice for working with very large DBs in Java. What we do is a kind of BI (business Intelligence), i.e analyzing very large DBs, and using them to create ...
0
votes
0answers
54 views

Converting large files in python

I have a few files that are ~64GB in size that I think I would like to convert to hdf5 format. I was wondering what the best approach for doing so would be? Reading line-by-line seems to take more ...
3
votes
1answer
102 views

Synthetic database records

Assume we are getting some statistics from a customer which we analyse and we send our comments to the customer. Now, the customer tells us that the statistic they computed between January and March ...
-1
votes
1answer
66 views

Storing a looong lookup table

Background The product i am working on has a very long lookup-table. the table contains static data and cannot be auto generated. there are about 500 rows and 10 columns. columns have mostly integers ...
0
votes
2answers
56 views

Is it good practice to keep 2 related tables (using auto_increment PK) to have the same Max of auto_increment ID when table1 got modified?

This question is about good design practice in programming. Let see this example, we have 2 interrelated tables: Table1 textID - text 1 - love.. 2 - men... ... Table2 rID - textID 1 - ...
0
votes
1answer
115 views

Inserting data to database from Android

I have to build an application where the requirement is that my clients will send data from their Android device and I have to save that data to a database. I have done the part of coding that ...
27
votes
4answers
4k views

Is backing up a MySQL database in Git a good idea?

I am trying to improve the backup situation for my application. I have a Django application and MySQL database. I read an article suggesting backing up the database in Git. On the one hand I like ...
56
votes
6answers
3k views

Is this a ridiculous way to structure a DB schema, or am I completely missing something?

I have done a fair bit of work with relational databases, and think I understand the basic concepts of good schema design pretty well. I recently was tasked with taking over a project where the DB was ...
0
votes
1answer
94 views

Can I use access used by Visual Basic for building a database [closed]

I am the only programmer where I work (summer job) and I am a student with only a few years of programming experience. So I was asked to build a database and I am very excited about this project ...
2
votes
0answers
53 views

Minimal set of critical database operations

In designing the data layer code for an application, I'm trying to determine if there is a minimal set of database operations (both single and combined) that are essential for proper application ...