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

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0
votes
1answer
15 views

How to design this better?

I'm developing a system using .NET which will be used by multiple users. Because of that, I need to identify on the database which data belongs to each user. Explaining with an example, imagine I have ...
-5
votes
0answers
38 views

How to use multi queries in PHP that can solve my problem? [on hold]

I have recently started doing PHP and MySQL. I've done a lot and now I was thinking to apply all my knowledge and build a very simple Social Network just for practice. I am doing it in object oriented ...
1
vote
1answer
79 views

Eventual consistency in Banking systems

I keep hearing people say Banking systems like ATM use Eventual consistency model for data synchronization, but I am wondering if it is true. Definitely the amount you withdraw might be delayed ...
0
votes
1answer
89 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 ...
0
votes
2answers
48 views

Delphi 7 using RAM for database

I have an existing database app written in D7 with apollo databases. The client has given me a fast desktop with 24gb ram Can I somehow load the database files into ram to speed up processing? With ...
1
vote
1answer
74 views

Advantages and disadvantages of making one DB per customer [duplicate]

I'm starting to design a web application, and I'm evaluating some decisions regarding the general structure of it. My use case is as follows: I plan to have multiple customers on a single server. ...
-2
votes
0answers
24 views

Scheme Advice, ways to improve

I'm gonna create a Student Information System with Laravel and MySQL. My two current planned tables are: enrollees & enrollees_detail enrollee id -> int last_name ...
1
vote
3answers
68 views

what are the things to take in consideration when designing a database that likely will be distributed after some time? [on hold]

We are small start-up now, we don't have a DBA. if our project succeed, it will have a lot of data that will likely need to be distributed over several machines. So we want to make that step easier, ...
1
vote
1answer
39 views

options for data analytics for time series store

I'm building an Internet of Things solution that has a number of real time feeds. I need to make a couple of design decisions with regards to the data store and reporting and looking for input. I ...
-3
votes
0answers
37 views

how to select a specific word in specific column php mysql [closed]

I have table with only one column that contains a text (200 char) and I want to select a specific word that comes after my keyword to use is in autocomplete for my textbox field. suppose that: row ...
0
votes
0answers
37 views

Sproc chaining verse discrete calls from OO code

I'm currently working on a change at work to generalize a function that was sloppily coded up to work for a particular use case. The function calls a particular sproc that checks if an entity exists ...
-2
votes
1answer
156 views

Backend choice for an AngularJS app [closed]

I'm developing an AngularJS app, and the frontend part is nearly finished. The next step would be the creation of a backend solution to create and manage users. The user has to be able to add/delete ...
-1
votes
0answers
50 views

Backend development [closed]

Being new to the programming world I've been learning for about a year now. Having a sometimes fragmented knowledge about programming and concepts I would like your guidance in this. I want to create ...
-2
votes
0answers
41 views

Mongo DB schema creation

I am creating a chat app. What I will have is A set of users who will chat with customerCare. A company holding different departments. A department holding different agents. Agents from various ...
2
votes
0answers
53 views

What are some important considerations when developing a DBaaS (DataBase as a Service)

I'm interested in creating a Database as a Service. I want users of the service to be able to do a few seemingly not very simple things. Sign up and be given access to a JSON datastore that they can ...
4
votes
1answer
147 views

Class instance clustering in object reference graph for multi-entries serialization

My question is on the best way to cluster a graph of class instances around specifically marked objects (objects are the graph nodes and the references to each other are the directed edges of the ...
0
votes
1answer
202 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
64 views

Trying to “combine” similar objects without doing a bazillion comparisons

In this database I have "accesses" - each access can have any number (usually less than 4, sometimes as many as 15) attributes. I also have "tickets" where N users are requesting M accesses, so I've ...
0
votes
1answer
63 views

Dropping database in Grails is too easy. How to prevent accidental drops?

I just dropped production database. It happened because I used dbCreate = "create" instead of "update" in DataSource.groovy. I was changing some domain models and wanted to update the database. ...
0
votes
3answers
74 views

How should the database schema be migrated?

I am using a bunch of freelance programmers to develop a web application. We are in the early stages of development, meaning that we are making many changes to our database schema. We have one test ...
1
vote
1answer
93 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 ...
78
votes
10answers
10k views

Why is “Select * from table” considered bad practice

Yesterday I was discussing with a "hobby" programmer (I myself am a professional programmer). We came across some of his work, and he said he always queries all columns in his database (even on/in ...
1
vote
1answer
150 views

Why are JOINS deprecated for a in-memory database?

Correct me if I'm misunderstanding. Refer to the following sentence: Stack Overflow copied a key part of the Wikipedia database design. This turned out to be a mistake which will need massive ...
3
votes
1answer
122 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
votes
1answer
36 views

Appending local MySQL data to same MySQL data in web server

my IT boss wanted this scenario to be undertaken: First, we develop an Alumni program using PHP and deploy this in the web server which can be accessed by that school alumni in the web to update their ...
0
votes
1answer
117 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 ...
1
vote
1answer
62 views

Lazy Loading, DAL and BLL abstraction

I'm asking myself a question to code the right way on a new fresh project. I have a designed database and I mapped tables to equivalent POCO classes using Entity Framework 6 Code First. Then, I ...
0
votes
0answers
33 views

Best approach for a server configuration data collection and reporting solution from a legacy script?

I have a project which involves collecting config data from windows servers in our (very large) server estate. My manager wants me to collect over 150 data items across all configuration areas ...
0
votes
1answer
87 views

Why doesn't MySQL have an explicit “No Limit” option for queries?

I use SQLyog Community edition and like many other SQL applications out there it puts a 1000 result limit on queries that do not have a limit provided. I am wondering why MySQL doesn't have an ...
4
votes
1answer
175 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 ...
7
votes
1answer
345 views

When allowing a user to change passwords, should I generate a new salt?

In my database, I have a column for the hashed password and the salt. My application allows users to change their password. Should I use the same salt for the password, or should I generate a new ...
0
votes
1answer
60 views

DB Design: How to link a single column to a collection of entities

I have a db design question that I am sure has been quite extensively covered but I cannot find a good answer already. The problem is how to efficiently link a single school course to a collection ...
0
votes
1answer
55 views

Dividing database between MySQL and NoSQL

Mine is a typical website developed with LAMP stack. Due to scalability issues we are planning to incorporate NoSQL for the application. For the implementation, we are planning to implement hybrid ...
4
votes
9answers
691 views

How do you decide between putting the code in the database or putting the code in the application? [closed]

For the sake of argument: Let's assume the application we are building is an amortization schedule. Let's also assume that the database has a table called tblAmortizationPayments that stores the ...
-1
votes
1answer
94 views

Should We Use Surrogate Primary Keys for Every Table? [duplicate]

We are developing a data model for a marketing database that will import transaction, customer, inventory, etc. files and the directive is ONE process that works for every client. We have been told ...
1
vote
1answer
81 views

How to compare and relate together the concept of DBMS to the concept of Cloud Storage system? [closed]

I am a student of Computer Science and I am writing my disseration on a Cloud Storage application developed in the company for wich I work. My problem is the following one: my supervisor (the teacher ...
0
votes
0answers
28 views

How to upload huge data into SimpleDB quickly? [migrated]

I have a 2GB text file. I want to upload this into Amazon SimpleDB. I am using SDBExplorer to bulk upload the data. However the upload process is taking a lot of time. You can only upload around 25 ...
1
vote
4answers
219 views

How do you call one program from another?

What I'm wondering is how running programs communicate with each other, and if someone could post some sample code for how to do this, so I can try it out myself, just for educational purposes. For ...
4
votes
3answers
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 ...
9
votes
2answers
1k views

What is the difference between collation and character set?

I have a general question about databases. We usually use the term collation with databases. I would like to know how its different from character set. I guess collation is a subset of character set. ...
0
votes
1answer
58 views

Does a data-driven application need a database?

This may be a terribly stupid question, but I can't find anything even related on Google (maybe I am not searching properly). I've been a developer for around a year now. I do desktop and web apps ...
1
vote
3answers
65 views

What are the use cases for these relationship types?

Use Case What are the use cases for creating a one-to-one relationship where the parent points to the child compared to a child pointing to the parent? If there is no difference, is one preferred ...
-2
votes
1answer
49 views

How to maintain trade off between number of columns in table vs join operations? [closed]

I have learnt that if there are more columns in table, then get those results using join query. How to decide the max number of columns in table? How feasible is "Join Operation" if too many table ...
4
votes
0answers
46 views

Continous Deployment and database format changes [duplicate]

My current automated workflow looks like this: I commit changes I push changes Build (actually just a lot of tests using mock database) is triggered If all tests pass, the new code is deployed to ...
0
votes
0answers
57 views

what should I save in local android DB to be more efficient and to last more than one session (and shouldn't be stored in the server only)?

I write an android app. The user sends the server its location and get places relevant to him. He then can up-vote or down-vote any offer. I wonder if I should write to local DB and when? I ...
1
vote
1answer
114 views

Processing csv files (alternative to business logic in DB)

We are working on a fulfillment system for an online book store. Everyday we receive tens of CSV files (about 90 files) with data about purchased orders. Example: OrderId | BookTitle | ...
0
votes
2answers
120 views

Moving data between databases with XML

I just read this quote online: XML is a very useful technology for moving data between different databases or between databases and other programs. However, it is not itself a database. Which is ...
0
votes
1answer
197 views

Beginning Data Mining

For simplicity, my database has entities and transactions. Each transaction has a DateCreated and a foreign key to the entity. I'd like to have the ability to find entities that have had a recurring ...
3
votes
2answers
165 views

What is a scalable and practical way to search existence of a group of strings in a huge file

Context: I built an app which generates around 1000 domain names based on user input. I need to check if they are available or not by matching against a huge zone file of parsed domain names which is ...
4
votes
2answers
327 views

How deeply programmer should know about internals of database engine? [closed]

I am learning SQL Server 2012 along with C#. In the past, I took database class in college, and have good grasp on SQL language and can write queries. However, looking at SQL Server documentation (or ...