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.

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26
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8answers
6k views

Are NoSQL databases going to take the place of relational databases? Is SQL going away? [closed]

Does anyone have experience with NoSQL databases (CouchDB, MongoDB, Google's BigTable, Dynamo, Cassandra...)? What was it like? Was it actual production/on the job experience? What will happen to ...
113
votes
14answers
23k views

“Never do in code what you can get the SQL server to do well for you” - Is this a recipe for a bad design?

It's an idea I've heard repeated in a handful of places. Some more or less acknowledging that once trying to solve a problem purely in SQL exceeds a certain level of complexity you should indeed be ...
9
votes
3answers
3k views

XML vs SQL for small projects?

I'm working on a small project which will only have one user at a time since it's a local application (developed in WPF and C#). To store data I was thinking of using an XML file but I'm wondering if ...
125
votes
13answers
59k views

Why use a database instead of just saving your data to disk?

Instead of a database I just serialize my data to JSON, saving and loading it to disk when necessary. All the data management is made on the program itself, which is faster AND easier than using SQL ...
89
votes
10answers
18k 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 ...
12
votes
3answers
757 views

Is reliance on parametrized queries the only way to protect against SQL injection?

All I have seen on SQL injection attacks seems to suggest that parametrized queries, particularly ones in stored procedures, are the only way to protect against such attacks. While I was working (back ...
21
votes
2answers
6k views

What's the history of the non-official pronunciation of SQL?

SQL is officially pronounced as /ˌɛskjuːˈɛl/ like "S-Q-L", as stated in Beaulieu, Alan (April 2009). Mary E. Treseler. ed. Learning SQL (2nd ed.). Sebastapol, CA, USA: O'Reilly. ISBN ...
12
votes
4answers
6k views

Maintaining referential integrity between a mobile client and a server

So I have a relatively simple system. A mobile client creates records in a sqlite database that I would like to have synced to a remote SQL server (that is shared with other mobile clients). So when I ...
9
votes
2answers
6k views

Why NoSQL over SQL? [duplicate]

Possible Duplicate: When would someone use MongoDB (or similar) over traditional RDMS? How well the SQL and NoSQL go head-to-head. I read somewhere that SQL databases are not well for data ...
10
votes
6answers
5k views

Code formatting SQL queries

Should I break SQL queries in different lines? For example in the project I am working on, we have a query that is taking 1600 columns! 1600 + tab chars. I wrote queries like this: "SELECT bla , ...
19
votes
7answers
2k views

Why is filesystem preferred for logs instead of RDBMS?

Question should be clear from its title. For example Apache saves its access and error logs in files instead of RDBMS no matter on how large or small scale it is being utilized. For RDMS we just have ...
19
votes
5answers
1k views

What good reasons are there to capitalise SQL keywords?

There seem to be a lot of developers who write their SQL by capitalising the keywords: SELECT column FROM table INNER JOIN table ON condition WHERE condition GROUP BY clause HAVING ...
16
votes
4answers
481 views

Database abstraction — is it being overdone?

After being exposed to numerous database abstraction layers, I'm starting to wonder what the point is of every library inventing their own different paradigm to access data. Picking up a new DAL feels ...
4
votes
2answers
2k 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 ...
144
votes
19answers
47k views

Why is naming a table's Primary Key column “Id” considered bad practice? [closed]

My t-sql teacher told us that naming our PK column "Id" is considered bad practice without any further explanations. Why is naming a table PK column "Id" is considered bad practice?
12
votes
5answers
8k views

What are questions to test a programmers knowledge of SQL? [closed]

What are questions to test a programmers knowledge of SQL? What is the answer to the question? And what would a lack of an correct answer mean in terms of time likely to understand the concept(s) ...
19
votes
6answers
42k views

SQL Triggers and when or when not to use them.

When I was originally learning about SQL I was always told, only use triggers if you really need to and opt to use stored procedures instead if possible. Now unfortunately at the time (a good few ...
58
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 ...
11
votes
9answers
6k views

Foreign key restrictions -> yes or no?

I would like to hear some”real life experience” suggestions if foreign key restrictions are good or bad thing to enforce in DB. I would kindly ask students/beginners to refrain from jumping and ...
4
votes
4answers
941 views

What are the arguments for/against Code Generation?

I'm in a position where we've got some brittle code that constructs SQL-like queries via text concatenation with parameters for inputs. The data source that it queries is fast and scalable but lacking ...
13
votes
2answers
3k 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 ...
13
votes
13answers
1k views

Do SQL Devs create SQL queries using SQL Query Designers?

I was just curious if SQL Devs write their code freehand or do they make use of the visual query designer to generate queries? In the majority of the cases, the query designer can create most of ...
7
votes
6answers
981 views

Is the “One Description Table to rule them all” approch good?

Long ago, I worked (as a client) with a software which use a centralized table for it's codified element. Here, as far as I remember, how the table look like : Table_Name (PK) Field_Name (PK) Code ...
6
votes
1answer
12k views

Entity Framework vs. Linq to SQL? [closed]

I'm a little bit confused about these two terms "Linq to SQL" and "Entity Framework". I have the general idea that both of them somehow allow you to refer to database tables as .net objects or ...
5
votes
9answers
25k views

Are certification courses worth it? [duplicate]

I'm planning on getting certification in Database Development for SQL Server (MSTC - 70-433). I'm a junior level report writer at a new job and the company is offering to pay the majority, if not all, ...
23
votes
6answers
2k views

Why SQL is not so widespread in large desktop applications?

As a software developer, I've worked on projects ranging from tiny home-made apps to medium-size enterprise applications. In nearly every project I used a database or regretted choosing not to use it ...
10
votes
6answers
1k views

What kind of Web development projects benefit from using ORM?

I'll start by saying that I've done 95% of my database work using SQL. Recently, I did some investigation of various ORMs, such as NHibernate and Doctrine. I can see the advantages of not needing to ...
7
votes
1answer
2k views

Raw Sql vs SqlAlchemy when Django ORM is not enough

In a django project, if a situation comes that Django ORM is not able to execute some complex queries then there are 2 options: Use Raw Sql queries Use SqlAlchemy I want to know if there are ...
2
votes
4answers
2k views

Should I be learning Linq, Direct SQL Commands (in .net), EF or other? [closed]

Basically, I have a very good knowledge of plain old SQL coming from Classic ASP programming. Over the past couple of months, I have been learning C# and today was my first full day at MVC 3 (Razor) ...
22
votes
2answers
9k views

self referencing tables, good or bad?

Representing geographical locations within an application, the design of the underlying data model suggests two clear options (or maybe more?). One table with a self referencing parent_id column uk - ...
7
votes
4answers
452 views

Direct database manipulation an anti-pattern?

Recently I learned that some teams have moved all their database manipulation to the actual database through the use of stored procedures. I thought that was pretty clever, since the database becomes ...
4
votes
6answers
2k views

Confusion about proper use of * wildcard in SQL [duplicate]

Suppose I was writing an address book application where the details of each contact were stored in an SQL database. A user wants to know all the details for a person whose name is "Bob [Someone]". ...
2
votes
1answer
99 views

What is the best way to store a formula in a database for a table driven formula? [closed]

So I am changing my code over to a table driven formula system to make it sustainable in the long term. So basically I have 5 foreign keys that will get me to a single formula to use. However I'm ...
1
vote
1answer
1k views

How can I implement a database TableView like thing in C++?

How can I implement a TableView like thing in C++? I want to emulating a tiny relation database like thing in C++. I have data tables, and I want to transform it somehow, so I need a TableView like ...
0
votes
3answers
482 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 ...
11
votes
2answers
563 views

Why store flags/enums in a database as strings instead of integers?

I've been browsing SQL dumps of some famous CMSes, including Drupal 7, Wordpress (some quite very old version), and some custom application based on Python. All of these dumps contained data with ...
5
votes
2answers
220 views

Storing stop/start points in a database

Let's say I am storing start and stop points per user into a database table. For example... let's say in a chat system, a user only needs to see lines 24-293, and 500-512. (Let's say he logged off ...
4
votes
2answers
484 views

Entity Framework with no direct table access

There are some similar questions I've found here, but none of them fully answer the question I'm asking. Similar questions: here and here In my company, I develop C# .NET applications and our Server ...
4
votes
3answers
347 views

Rule of thumb for field sizes

What VARCHAR sizes should be used for first and last names, phone numbers (preferably international), email adresses, urls, dictionary words and file names? Edit: Zapped the introductory phrase to ...
4
votes
2answers
184 views

When and how much should we validate input when working with (C)AP storage?

Herein, we consider a server-client architecture. Suppose we keep the details flexible, but there's more than one layer of servers supporting our hypothetical service. The general question is "When ...
3
votes
3answers
472 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 ...
3
votes
2answers
2k views

Why is NoSQL better for this scenario?

Hypothetical scenario: Let's say we are downloading JSON from Facebook with details of a user's friend's checkins, posts, etc... These come in as one document per friend per activity, so with 8 ...
3
votes
1answer
601 views

How would one build a relational database on a key-value store, a-la Berkeley DB's SQL interface?

I've been checking out Berkeley DB and was impressed to find that it supported a SQL interface that is "nearly identical" to SQLite. ...
2
votes
3answers
128 views

At which point using string-based enums can become a real problem?

This is a direct follower to this question. An answer given to that questions says (my understanding), that nowadays using string-based enums instead of integers isn't a much problem, because hosting ...
1
vote
3answers
334 views

Best OOP pattern to use for creating a commandline SQL API for a proprietary json based company datastore

We need to create a SQL commandline tool for querying a proprietary json based datastore. I'll be using java. Any suggestions on the primary OOP design pattern I should use for building this API? ...