Structured Query Language (SQL) is a language for managing data in relational database management systems. This tag is for general SQL programming questions; it is not for Microsoft SQL Server (for this, use the sql-server tag), nor does it refer to specific dialects of SQL on its own.

learn more… | top users | synonyms

4
votes
3answers
544 views

Is it better to use a switch statement or database to look through 5,000 to 10,000 instances?

I have some JSON data in this format (5,000 instances for now): {"id":"123456","icon":"icon.png","caseName":"name of case"} I am allowing the user to search for the name of the case and then return ...
4
votes
4answers
812 views

Choosing value in SQL query vs (Java) code

I need to choose one of three values of an integer using the value of a column on a nullable column of a table. There are at least two approaches: 1) use SQL to do all the work: test null values, and ...
0
votes
3answers
145 views

High-Level SQL Interoperability

In a server -> client scenario, wouldn't it be simpler and faster to grant a public user access to a Stored Procedure rather than using web services (XML, REST, SOAP, etc) and other interoperable ...
0
votes
1answer
886 views

How to combine Google Analytics with Relational Database

I have a website with quite a lot of registered users, they are stored in a PostgreSQL database. I also running Google Analytics on the website to track the users. Is there a way to individually ...
2
votes
1answer
368 views

Creating a online database creator

I've been thinking of creating an online database creator (think DabbleDB, Zoho Creator, Intuit Quickbase, etc.). I've been thinking of a couple solutions: Have 4 database tables: Tables, Rows, ...
0
votes
4answers
198 views

When to store Date/DateTime?

I'm working on a social network website and I'm not quite sure when I should store the date/datetime. The service includes some of the following events: Register/Login Follow "Like" (images & ...
2
votes
1answer
220 views

Mental schema for SQL queries [closed]

While preparing SQL introductory material, I've ended asking myself about the line of thought followed by a developer when writing a query. I believe it could be too valuable from a beginner's point ...
-3
votes
1answer
218 views

Finding next free IP in a network

I have an IP network and want to automatically find a free IP address to provision a new server. Due to frequent server additions/removals the used IPs might be quite fragmented over the whole address ...
2
votes
0answers
266 views

Match buyers and sellers based on date ranges and quantity of shares

NOTE: This is in reference to the question I asked on Stack Overflow but was told to post this here I'm building a trading application that matches buyers/sellers that own subscription. Subscriptions ...
3
votes
5answers
252 views

Violating SQL principles

I have to write a decent size database, 1GB more or less. I have only taken an introductory semester regarding SQL databases. During the course we learned that the relational model under SQL has no ...
-1
votes
2answers
544 views

Lead developer unable to do INNER JOIN [closed]

I had worked in the past for a small company developing web applications. Back then the current lead developer, who is also one of the bosses, told me that he is incapable of making a JOIN inside a ...
1
vote
2answers
1k views

Database Context and Singleton injection with IoC

All of the below relates to a ASP.NET c# app. I have a Singleton Settings MemoryCache that reads values from database on first access and caches these, then invalidates them using SQL Service Broker ...
1
vote
0answers
311 views

What database structure is suitable for tracking File audits?

I need to track permissions and access requests to a file server in a database. I'm given the full path of the folder and am considering parsing the path (splitting on the "/" character) and creating ...
2
votes
2answers
148 views

SQL Query syntax - formatting?

I'm looking at a very large (5-6 digit LOC), very complex, code-base, full of interacting bulky, interdependent, views and stored procedures (multiple 4-5 digit count silos). The source SQL has been ...
4
votes
3answers
563 views

How to avoid unmaintainable code when using SQL in an MVC setting?

I want to present a list of products to the user. This list is paginated and can be sorted by the user by product ID or product name in ascending or descending order. I am using an MVC setting, where ...
0
votes
1answer
869 views

How exactly can I check for new rows in sql with ajax? [closed]

How do certain services, just like google plus and facebook, check for new content without reloading the page? Whenever you are on any of those websites a new notification of a post related content ...
1
vote
1answer
244 views

How to store Status for Reservation table

I have a reservation table (a user fills out a form to request a reservation). It has two parts that need to be confirmed. isReservationAccepted (decline,accept,waiting) and hasReservationBeenSent (...
0
votes
1answer
222 views

Queries in three tier architecture

I am wondering where should the DB queries need to be in the three tier architecture. The first association that think is in the DAL. But then if the BL want to search for an object, the DAL need to ...
22
votes
2answers
2k views

Internal-use websites: Is there a compelling case against SQLite?

Many web frameworks, such as Flask or Django use SQLite as their default database. SQLite is compelling because it's included in python, and administrative overhead is pretty low. However, most high ...
0
votes
1answer
458 views

Search for object in loop or query? Who has better performance?

I have a DB that stores some complex objects of my app. When my app starts I load the objects into list and store them on the RAM. But sometimes I would like to search for an objects that fulfills ...
5
votes
3answers
492 views

Consequences of “naïve” vs “naive”?

While using IE autocorrect "naive" got transformed to "naïve"! My regional settings are Au English, from a Unicode search point of view the two are nothing alike. I am not even sure whether there are ...
0
votes
1answer
100 views

Multiple schemas vs aditional column per customer

If you have different database per customer as there is no need to share any data between them does the same apply if a customer has multiple stores ? I believe that it is easier to do queries for ...
1
vote
1answer
1k views

Notify client about changes in database in Java

I'm working on a distributed client-server system that uses TCP. The program's functions is to transfer money to an from the server, but also between the clients, a sort of MobilePay. When one ...
0
votes
1answer
186 views

SQL-99 specification, is it specified to first order the result and limit it afterwards?

If I wrote this in MySQL SELECT * FROM foo ORDER BY bar LIMIT 1 it would first order the result and limit it afterwards. I always get the lowest bar. I wonder if this is specified like this in SQL-...
8
votes
1answer
350 views

Can relational algebra/calculus proofs be used to test/verify SQL?

Is it feasible or even possible to use relational algebra and/or relational calculus in the form of proofs to test/verify the correctness of SQL statements, functions, and stored procedures? It seems ...
7
votes
5answers
351 views

In retrospect, has it been a good idea to use three-valued logic for SQL NULL comparisons?

In SQL, NULL means "unknown value". Thus, every comparison with NULL yields NULL (unknown) rather than TRUE or FALSE. From a conceptional point of view, this three-valued logic makes sense. From a ...
3
votes
1answer
222 views

Best way to rename existing unique field names in database?

I have a database table that contains id, filename, userId id is unique identifier filename should also be unique table may contain >10000 records When a user uploads a file it should be ...
4
votes
2answers
4k views

Database model for keeping track of likes/shares/comments on blog posts over time

My goal is to keep track of the popular posts on different blog sites based on social network activity at any given time. The goal is not to simply get the most popular now, but instead find posts ...
1
vote
1answer
392 views

Store data for multiple User Type

I am developing an app where four types of user share same module. So is it a good idea to create: one table and user_type and user_id (something like that) table prefixes basically 4 diff tables of ...
2
votes
2answers
183 views

Configurable tables in SQL database

I have the following tables in my database: Configuration Table: ====================================== Start_Range | End Range | Config_id 10 | 15 | 1 ============================...
14
votes
3answers
5k views

Is inline SQL still classed as bad practice now that we have Micro ORMs?

This is a bit of an open ended question but I wanted some opinions, as I grew up in a world where inline SQL scripts were the norm, then we were all made very aware of SQL injection based issues, and ...
1
vote
1answer
136 views

structure problem in Relational DBMS creation

For learning and understanding purpose, I currently want to try to make a small relational DBMS with simple features like (for now) only sequential reading/writing and CREATE TABLE, INSERT, SELECT, ...
16
votes
2answers
5k views

SQLite with two python processes accessing it: one reading, one writing

I'm developing a small system with two components: one polls data from an internet resource and translates it into sql data to persist it locally; the second one reads that sql data from the local ...
3
votes
4answers
2k views

Database is performing slow, even all the tables are having normalization

An interviewer asked me this question: Tables are created with appropriate normalization rules, However the database is performing slow. [Ie.: The select, insert statements are taking time to do ...
0
votes
1answer
1k views

C# Design for SQL connection and commands

Currently I'm working on system that works with database, and I would like to have it done elegant way. So I have abstracted DBConnection into one class, DBCommands into another class. (DBCommands : ...
10
votes
7answers
698 views

Nested Entities and calculation on leaf entity property - SQL or NoSQL approach

I am working on a hobby project called Menu/Recipe Management. This is how my entities and their relations look like. A Nutrient has properties Code and Value An Ingredient has a collection of ...
18
votes
4answers
2k views

Why many designs ignore normalization in RDBMS?

I got to see many designs that normalization wasn't the first consideration in decision making phase. In many cases those designs included more than 30 columns, and the main approach was "to put ...
1
vote
3answers
664 views

What would be a good “umbrella” term for HTML, CSS, SQL, JavaScript and the like? [closed]

There appears to be a pretty clear consensus on the question about whether HTML and CSS are programming languages. They are not. HTML is a markup language and CSS is a stylesheet language. You could ...
4
votes
2answers
2k views

Best practice in application design / SQL authentication

I am currently involved in the implementation/design of an existing application for a large scale customer. The application has a similar model as e.g. vCenter Server whereby a number of components ...
1
vote
3answers
6k views

Using Autoincrement Primary keys as Foreign Keys

When creating a table, there is an option for us to set the numeric primary key as autoincrement where it's value increases whenever a new data in inserted. This primary number can be used for ...
9
votes
9answers
4k views

Why don't RDBMSes return joined tables in a nested format?

For example, say I want to fetch a User and all of his phone numbers and email addresses. The phone numbers and emails are stored in separate tables, One user to many phones/emails. I can do this ...
0
votes
2answers
420 views

Automating database deployment using a CMS

My team are developing Umbraco websites and looking to improve the automation of our database deployment. Currently we have automated builds and deployments of our source code using Kiln and Team ...
0
votes
2answers
332 views

Best practices for rotating large datasets?

[edit]Turns out there's 1.5 million records... The SQL database is taking about 17-20 seconds to run the query. Would it be best to have Java handle the joins and rearranging in that case? Since this ...
1
vote
1answer
263 views

What's the best approach to building a db schema for profile, but to track changes?

I'm working on a site where companies can create a profile then add locations for each profile. Those first two tables are simple enough. But any changes to their profiles or locations have to go ...
4
votes
2answers
1k views

Logic design question for SQL query

Was wondering if you could help me on a SQL problem I’m having. I have a set of records of events where each event has a start time and end time. No event has the same start time, and the end time ...
4
votes
5answers
4k views

Is SQLite a sensible option for data logging?

I am trying to setup a small data-logging application under linux. The data arrives via serial port, and from there it should be pumped to logging and to graphical display. The logging functionality ...
2
votes
1answer
1k views

Status update & news feed database design / architecture

Imagine a application similar to Facebook, where you have status updates and a news feed. The names and profile pictures can be changed. There are also several different types of updates requiring a ...
0
votes
1answer
618 views

Different ways to generate the latest int type primary foreign key in code

I am new to sql. I have added 2 new tables in database. The primary key of first is a foreign key in the other. The type of the keys is integer. Now I want to generate the keys in the code and assign ...
8
votes
2answers
3k views

In what order are rows fetched absent ORDER BY clause?

One programmer is testing and comparing the same application which uses the same database structure, and the same data, only in two separate databases, one with Oracle 8 and one with Oracle 9. The ...
0
votes
1answer
787 views

Are there any SQL servers that support compiled queries?

Can SQL queries be compiled into byte code or equivalent to enhance performance? I know that most database servers support prepared statements, but is that the same thing as compiling? Most ...