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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One of my team members committed SQL injection-vulnerable code; should I report it to the manager? [closed]

One of my team members committed a huge mistake; a clear SQL injection-vulnerability. It obviously didn't pass my peer review and I made very clear that this is unacceptable. I never saw this ...
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3answers
1k views

Using SQL queries in loops

Is it a bad idea? I need to compare each entry.Key value in a Dictionary of strings to a SQL table. If there is a match, then I pull the data from that row. I was originally going to use a foreach ...
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2answers
474 views

Storing Dates & Times in SQL [closed]

I have a tool that I am working on which allows people to create meetings. They can select the Date, Time & Timezone that this meeting is occurring in. I need to determine the best way to store ...
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2answers
2k views

Clients connect to WCF or SQL Server

I was wondering what is the prefered way of accessing data from a server in a client application. The data will be stored on the server in an SQL database and I have previously used the following 2 ...
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3answers
520 views

What kind of user info is ok to be stored as plain text in SQL Database?

I'm practicing around building e-commerce asp.net applications that allows for users to register to the site and their user credentials are stored in a MySQL database. In my sample project the ...
3
votes
3answers
977 views

ASP.NET MVC should I reference the DAL from the UI?

I am developing an ASP.NET MVC application, and I have three projects: UI (with the system.web.mvc reference, BL and DAL references) BL (business facade and business objects) DAL (contains my ...
0
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2answers
144 views

Sending a notification to each participant 3 hours before the meeting starts

Let's assume an application that deals with meetings where some users will participate. What is an efficient way to achieve this use case: 3 hours before the meeting should start, one reminder mail ...
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4answers
1k views

Historical precedent for why Prolog is less popular than SQL in Imperative Programming? [closed]

It seems that writing Declarative SQL is very popular in Imperative Programming. However, it also seems that writing Declarative Prolog could save a lot of complexity but this is not very common. ...
0
votes
1answer
54 views

Django Project Logic Solution

I'm starting to develop my first webapp, and I'm using django. Before anything I'm working on the software logic, how it should work, the links and objects it needs. The problem is: I need the app ...
4
votes
4answers
1k views

Organise C++ classes around SQL database

My question is about how best to organize C++ classes around a database model, and I understand this may appear very elementary. The software I propose to create will do the following. It is intended ...
2
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5answers
407 views

Stored Procedures, ORMs and other application layers

I'm just starting out on a project to develop a new, fairly substantial web application which has an underlying MSSQL database. We're hiring a team of developers to write the application (in .NET) and ...
3
votes
2answers
296 views

An algorithm that spreads similar items across a list

I need an algorithm that distributes same items across a list, so maximizing the distance between occurrences. E.g. I have a list of 15 items: {a,b,c,c,c,d,e,f,f,f,g,h,h,i,j} The algorithm should ...
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2answers
93 views

Efficient database access for related data

As an example for this question, consider a content management system that has a content database table which contains things like the page title and location as well as the content itself which could ...
2
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2answers
658 views

Combine union with distinct

Situation: I need distinct results from two tables, that both have duplicates. I would like to know if I should combine UNION and DISTINCT. Example 1 - Only use distinct SELECT DistinctValue FROM ...
1
vote
1answer
291 views

Should ORM data access methods be wrapped or used directly?

We're using an internally-built ORM. Each table is represented by a Model class, which inherits from a base model class that has a handful of methods like GetAll, GetWhere (to get rows with specified ...
17
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4answers
16k views

Why is SQL's BETWEEN inclusive rather than half-open?

Semi-open (or Half-Open, Half-Closed, Half-Bounded) intervals ([a,b), where xbelongs to the interval iff a <= x < b) are pretty common on programming, as they have many convenient properties. ...
37
votes
3answers
2k views

Why is most SQL written in YELLING? [duplicate]

On MySQL at least, the following two queries are functionally identical: select * from users limit 0, 1000; SELECT * FROM users LIMIT 0, 1000; However, most example sites and most developers I've ...
13
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6answers
6k 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 , ...
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1answer
2k views

SQLDatabase: Read a lot of data at once and process in memory or read the data when I need it?

I'm not sure how to approach this problem. I require a big chunk of data records from the SQL server. This chunk is based on variables, so I don't know before what records I need. I need to do a large ...
20
votes
3answers
67k views

Why do we need to put N before strings in Microsoft SQL Server?

I'm learning T-SQL. From the examples I've seen, to insert text in a varchar() cell, I can write just the string to insert, but for nvarchar() cells, every example prefix the strings with the letter ...
15
votes
7answers
726 views

To Domain or not to Domain

The SQL92 and SQL99 standards define CREATE DOMAIN DDL constructs. Not all databases support this, or have a different name for it (SQL Server has User Defined Types, for example). These allow one to ...
1
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1answer
60 views

Custom Domain or Attribute Reference Table or Both?

I'm designing my first real database and I'm weighing the pros and cons of how to enforce uniformity in my data. My first option is to create a custom domain and program my UI to only allow certain ...
3
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3answers
321 views

Is there a 'standard' SQL that can replace all the various custom versions?

I have been writing SQL for over 10 years now. I am extremely proficient at it and have experience working in SQL Server, Oracle, MySQL, PostgreSQL, etc. While there are multiple standards out there, ...
15
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4answers
4k views

Databases: Where should the application logic run? [duplicate]

http://highscalability.com/blog/2010/11/9/facebook-uses-non-stored-procedures-to-update-social-graphs.html talks about how Facebook moved logic out of the database into the application in order to ...
7
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7answers
384 views

Logistically, how do you manage embedded SQL?

My current application is running into issues with its ORM, and we're relying on some pretty hairy SQL to express queries that the ORM can't. Are there best practices in terms of how to manage the ...
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0answers
126 views

An algorithm to implement SQL's ORDER BY with TOP/LIMIT or OFFSET/FETCH

Is there a general algorithm to implement SQL's ORDER BY with OFFSET/LIMIT more efficiently than sorting all the records? The algorithm for a simple TOP x is easy enough. It takes one full pass ...
3
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2answers
307 views

Does ODBC require any run-time software beyond an .exe file to run against MySQL and ORACLE SQL? [closed]

I'm writing a software [under Windows] in C++ which later needs to be able to connect to both MySQL and ORACLE SQL. Now the software needs to be as simple for the user as possible. Now I'm ...
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2answers
463 views

Is it a bad practice to keep database schema scripts (DDL) and manipulation (DML) scripts in different modules

we have a project structure like the following "module-shared" module depends on "module-database" module and some other modules depend on "module-shared" but no other module depends on ...
2
votes
3answers
455 views

Managing database schema for a C++ app

I have an open source project (Cockatrice) that uses mysql for the server component. I'm planning some changes to the schema, but right now the only management I have is a script that runs the proper ...
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0answers
46 views

Database conceptual Question [duplicate]

When querying in database through PHP, is it good to open mysql connection before every query and close it as the query completes? or should we open the mysql connection as soon as the first query ...
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vote
2answers
141 views

Best way to store revision information for quick access to view or revert changes

What I am looking for is the most optimal solution for storing content revisions in an MSSQL database. We have an application that allows users to make changes to small HTML content blocks similar to ...
0
votes
1answer
224 views

MongoDB: Replicate data in documents vs. “join”

Disclaimer: This is a question derived from this one. What do you think about the following example of use case? I have a table containing orders. These orders has a lot of related information ...
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2answers
355 views

An algorithm for finding subset matching criteria?

I recently came up with a problem which I would like to share some thoughts about with someone on this forum. This relates to finding a subset. In reality it is more complicated, but I tried to ...
0
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1answer
327 views

Refactoring a Single Rails Model with large methods & long join queries trying to do everything

I have a working Ruby on Rails Model that I suspect is inefficient, hard to maintain, and full of unnecessary SQL join queries. I want to optimize and refactor this Model (Quiz.rb) to comply with ...
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0answers
192 views

embedding LEFT OUTER JOIN within INNER JOIN

I am having some problems with one of the question's answered in the book "SQL FOR MERE MORTALS". Here is the problem statement Here is the Database Structure Here is the answer which I am ...
13
votes
3answers
2k views

Best way to organize SQL queries stored in your code ? (or should you?) [closed]

I am sure I am not the only one who gets frustrated when they see a page of code littered with SQL queries. The ActiveRecord and other ORM patterns help mitigate a good amount of SQL used in a ...
4
votes
2answers
807 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 ...
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2answers
80 views

Changing an int to be a string in PHP / MySQL Schema

Background I'm trying to decide the best way to manage a change in requirements. Currently when an admin is assigned to a ticket, the ticket header record is given an owner and the ownerID field is ...
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2answers
74 views

Managing unique data correctly in SQL

Here in Brazil we have a personal identifier called CPF. This identifier has a sequence of 11 digits and is unique for each Brazilian citizen. Possibly in other countries there is something like that ...
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2answers
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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
1k views

Web-app filtering information client-side vs server-side?

I have a web-app that provides data (that is updated on an interval) for intranet users, who are able to filter information by location. I was having a discussion with a co-worker about whether that ...
0
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0answers
315 views

Javascript and SQL Lite (multi browser offline SQL/database query)

I'm in the elections division of my county and am trying to simplify a voter lookup method for our poll judges during election time. Currently we are using a clunky heavy application that the judges ...
0
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1answer
336 views

Full Text Indexing Strategy for MS Excel Documents

Background As part of a broader application that allows users to search thousands of MS Office documents on a private network, I need to index and make searchable Microsoft Excel files. My basic ...
2
votes
1answer
3k views

When deciding a Primary Key, can I use Date part of a DateTime field

I'm designing a payroll system I have designed a database with several tables and this question is related to following tables EMPLOYEE (Employee_ID [pk], Name,... etc) LOCATION (Location_ID [pk], ...
0
votes
1answer
495 views

Simplifying data search using .NET

An example on the asp.net site has an example of using Linq to create a search feature on a Music album site using MVC. The code looks like this - public ActionResult Index(string movieGenre, string ...
1
vote
1answer
239 views

Dynamic Query Generation : suggestion for better approaches [closed]

I am currently designing a functionality in my Web Application where the verified user of the application can execute queries which he wishes to from the predefined set of queries with where clause ...
59
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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 ...
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2answers
1k views

Large MySQL Batch Inserts From PHP: Run insert from script, or save as SQL file?

We have a large dataset that's current residing in many, many spreadsheets. I've been tasked with getting part of that data into our MySQL DB. When all is said and done, I will probably be inserting ...
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3answers
199 views

Store history in SQL database column

We have a database that stores the process/history of particular machines. What I mean by that is that we have "started", "updating", "shutdown", and so on for all the computers in the company. The ...
7
votes
4answers
569 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 ...