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

1
vote
1answer
878 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 ...
1
vote
5answers
4k views

Externalising SQL Queries in Java

What are the advantages and disadvantages of externalising SQL queries in Java (or similar general-purpose object-oriented programming language. Externalizing means storing all SQL in a separate ...
4
votes
2answers
325 views

Proper Data Structure for Commentable Comments

Been struggling with this on an architectural level. I have an object which can be commented on, let's call it a Post. Every post has a unique ID. Now I want to comment on that Post, and I can use ...
11
votes
4answers
990 views

TDD with SQL and data manipulation functions

While I'm a professional programmer, I've never been formally trained in software engineering. As I'm frequently visiting here and SO, I've noticed a trend for writing unit tests whenever possible ...
4
votes
3answers
688 views

Appropriate use of SQL CLR

We have some back end processes that runs* on our sql server (SQL Server), they involve processing claims. This requires both data manipulation (biz logic) and data read/write to tables. The biz ...
1
vote
2answers
633 views

Registration: Email hash and verifying only one account per email

I'm using a registration function that hashes the email in PBKDF2 with a random and unique Salt each time. The hashes email and his salt are saved in the DB. No problem with that. The problem is that ...
2
votes
1answer
733 views

Best way to remove list items from an existing record

Ok more of a conceptual question here: Say I have an existing record of type Meeting. When I go to edit the meeting I have a listbox with all current meeting participants, and one with all employees. ...
11
votes
4answers
6k 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. ...
7
votes
2answers
2k views

Best method to implement a filtered search

I would like to ask you, your opinion when it comes to implement a filtered search form. Let's imagine the following case: 1 Big table with lots of columns It might be important to say that this SQL ...
3
votes
3answers
428 views

Why should I add CHECK CONSTRAINT?

Following is a table creating script created by Entity Framework using the model shown in http://codereview.stackexchange.com/questions/14077/is-it-proper-tpt-inheritance. In this script, there are ...
3
votes
2answers
223 views

Having 2 Initialize Paragraphs in 1 COBOL program

I am designing a COBOL program that does 2 things. 1 reads specific rows from a table, and inserts a new row based on the original. 2 reads different rows from the same table, and updates those rows. ...
1
vote
2answers
111 views

Cataloging events, projects and tasks: Is SQL appropriate?

I have this idea for a database: it would hold everything I "need to remember", and allow future coding projects to access the information. These future projects include a day-planner and historical ...
1
vote
3answers
406 views

Is an API in C++ a better alternative to computing directly in SQL?

I need to perform large amounts of computations on data storerd in a busy Microsoft SQL server. Would it be faster if I retrieve the data from the server, perform the computations locally in C++, and ...
13
votes
3answers
27k 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 ...
2
votes
2answers
178 views

Better way to search for text in two columns

Here is the scenario. I am making a custom blogging software for my site. I am implementing a search feature. It's not very sophisticated - basically it just takes the search phrase entered and runs ...
2
votes
8answers
6k views

Is executing SQL through a WebService a really bad idea?

Typically when creating a simple tool or something that has to use a database, I go through the fairly long process of first creating a webservice that connects to a database then creating methods on ...
0
votes
3answers
371 views

Does connection pooling work fine to execute 60 DB queries to load a page?

We use Linq2Sql in an ASP.NET application. Unfortunately the eager-loading in Linq2Sql isn't as powerful as in Entity Framework, so a lot of the data has to be lazy loaded as needed. Taking ...
4
votes
1answer
414 views

What is Rainbow (not the CMS)

I was reading this excellent blog article regarding speeding up the badge page and in the last comment the author waffles (a.k.a Sam Saffron) mentions these tools: dapper and a bunch of custom ...
0
votes
1answer
1k views

Database Driven Web Application, C# Front-End and F# Back-End meaning

Hi I am an intern working with ASP.NET. My current task is to make a website which will incorporate some jquery viewing features. This project seems to me will be primarily dealing with reading data ...
0
votes
3answers
1k views

Is this overkill? Using MDX queries and cubes instead of SQL stored procedures

I am new to Microsoft's SQL Server Analysis Services Cubes and MDX queries. Where I work we have a daily sales table in SQL Server 2005 that already contains an aggregate of sale information per ...
2
votes
1answer
578 views

Which would be a better way to load data via ajax

I am using google maps and returning html/lat/long from my MySQL database Currently A user picks a business category e.g; "Video Production". an ajax call is sent to a CodeIgniter controller the ...
1
vote
2answers
488 views

SQL language drawbacks, The Third Manifesto

Sometime ago I read about SQL language drawbacks (the basic language specification, not vendor specific), and one of the drawbacks was that the language does not allow to create a set of tuples that ...
5
votes
5answers
378 views

Alternatives for comparing data from different databases

I have two huge tables on separate databases. One of them has the information of all the SMS that passed through the company's servers while the other one has the information of the actual billing of ...
0
votes
2answers
317 views

Will TSQL become useless because of new ORMs? [closed]

By introducing LINQ to SQL, I found myself and my .NET developer colleagues gradually moving from TSQL to C# to create queries on the database. Entity Framework made that shift almost permanent. Now ...
2
votes
5answers
3k views

SQL Strings vs. Conditional SQL Statements

Is there an advantage to piecemealing sql strings together vs conditional sql statements in SQL Server itself? I have only about 10 months of SQL experience, so I could be speaking out of pure ...
1
vote
1answer
5k views

how to compare two large sets of data using PL/SQL?

I have two different tables in two separate databases with around 1.5 million records each. (BTW: im working on oracle databases) The objective is to check if every record present in table A is ...
3
votes
1answer
508 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. ...
1
vote
1answer
310 views

Implementing Bulk Update feature and its trade offs

The feature to implement is to allow a user to select items and apply data update in bulk. It is very similar to JIRA's ability to bulk update a list of selected issues. In my case: I iterate over ...
5
votes
2answers
343 views

Good architecture for user information on separate databases?

I need to write an API to connect to an existing SQL database. The API will be written in ASP.Net MVC3. The slight problem is that with existing users of the system, they may have a username on ...
5
votes
5answers
2k views

Two database fields for date and time - should they be merged?

In the following question, field and table names have been changed to protect their identities. If I have two database columns: MONKEY_DATE DATETIME NULL (with data e.g. 2012-05-14 00:00:00.000) ...
4
votes
3answers
335 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 ...
3
votes
4answers
190 views

What's the utility of encouraging users to learn SQL and possibly the ability to execute it?

Facing a situation where I can't possibly get all the features that are requested into each version of the LOB I support, I've evolved a number SQL query templates that users have and send to me, ...
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]". ...
26
votes
7answers
39k views

How do I make complex SQL queries easier to write?

I'm finding it very difficult to write complex SQL queries involving joins across many (at least 3-4) tables and involving several nested conditions. The queries I'm being asked to write are easily ...
1
vote
2answers
1k views

Designing complex query builders in java/jpa/hibernate

I need to build complex sql queries programatically, based on large filter conditions. For example, below are few sample/hypothitical filter conditions, based on which i need to fetch users Country: ...
2
votes
2answers
347 views

Where should SQL/DB Queries be encapsulated in a software system?

I frequently write small applications (either web based or otherwise) that require heavy database usage. i've attempted various ways of handling where to put the actual sql queries (sort of ad-hoc ORM ...
1
vote
2answers
639 views

SQL DB design to support user feeds (in application like facebook)

I have a social network server with a MySql DB. I want to show the users feeds like done in Facebook. Example - UserX now Friend with userY, userX did like on postX etc. Currently I have table: C1 : ...
9
votes
6answers
560 views

Software solution from the 2000's, should I attempt to patch or remake the whole thing?

I was sent out to discuss a system that a certain company is currently using and what should be done with it. The company manufactures various carton displays. This system was developed to keep track ...
3
votes
7answers
4k views

What is the best approach for database design with lots of columns?

I am writing a query based financial application. It lets the user to write complicated equations (much like WHERE part of an SQL query) and find companies matching those criteria. For the above, I ...
4
votes
4answers
2k views

Can NoSQL databases be used in e-commerce companies for order management?

Is it possible to use a non relational database be in an Order management system for an e-commerce company with a large number of orders everyday, like Amazon? Can the benefits of Non Relational ...
0
votes
4answers
212 views

Is it possible (or desirable, if not) to make an database engine organize the order of sql statements to maintain the referential integrity?

Today at work I found the following situation: We had two tables, A and B, with B having a foreign key linked to the primary key of A. On our application, we got two main situations that created ...
6
votes
5answers
2k views

What are the advantages to using SQL query builders?

Are there any advantages to using a query builder, rather than using raw SQL? E.g. $q->select('*') ->from('posts') ->innerJoin('terms', 'post_id') ->where(...) vs: SELECT * FROM ...
3
votes
7answers
215 views

Throwing an Exception if a Query Doesn't Use an Index

I'm working on a largish webapp that was developed by several other programmers and I keep running into performance issues caused by poorly written SQL queries and queries that don't use an index. ...
0
votes
1answer
165 views

Recommendation for a database to query records with attributes that are arrays or hashes?

I'm building site with a very simple data structure: documents that are nodes that reference other nodes that each have arrays of parents, children and siblings, so the structure is: Node: uuid name ...
6
votes
7answers
350 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 ...
2
votes
1answer
577 views

Sanity of design for my in-memory object representations of database rows

I've been trying to revise the structural design of the C#.NET-based system I'm currently working on. The new design involves a rather light-weight object-relational mapping framework (we're trying ...
8
votes
5answers
895 views

Why is SQL known as a relation-based / functional language?

We're learning that most languages are classified as either of the two, "relation based" or "high level". I've never used SQL before, but from reading its syntax it seems more like the ...
4
votes
2answers
613 views

Is a traditional client app which connects directly to a database a good idea?

After using Django's excellent admin interface, I was pondering creating a similar system which wasn't as tied to an ORM. Now, while considering this, I thought that overcoming webapps limitations ...
9
votes
4answers
3k 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
4answers
7k views

Best way to maintain data between local and remote sql databases

So I have, what would seem like a common question that I can't seem to find an answer to. I'm trying to find what is the "best practice" for how to architect a database that maintains data locally, ...