Q
Problem solve Get help with specific problems with your technologies, process and projects.

# Creating record set of time intervals by subtracting timestamp from the previous one

I have a table containing a timestamp. How can I generate a recordset containing the time interval by subtracting...

the timestamp column of the current record with the previous, assuming I've put the set in order of date?

If you were solving this problem procedurally, you could store the last date in a variable as you iterated through the ordered rows, however, SQL requires a different approach. For every row, simply take the difference between the date and the date which precedes it. I should note that this happens to be MS SQL Server flavored SQL.

```create table Things
( ID numeric,
SomeDate datetime );

insert into Things values (1,'01-JAN-2002 12:34PM');
insert into Things values (2,'01-JAN-2002 1:10PM');
insert into Things values (3,'01-JAN-2002 2:59PM');
insert into Things values (4,'01-JAN-2002 3:17PM');
insert into Things values (5,'01-JAN-2002 3:20PM');
insert into Things values (6,'01-JAN-2002 6:39PM');
insert into Things values (7,'01-JAN-2002 6:40PM');

select ID, SomeDate,
cast( SomeDate ? ( select max(SomeDate) from Things
where SomeDate < t.SomeDate )
as float
) * 24 * 60 as MinutesSinceLastDate
from Things t;

ID SomeDate                MinutesSinceLastDate
-- ----------------------- --------------------
1  2002-01-01 12:34:00.000 NULL
2  2002-01-01 13:10:00.000 36.000000000000007
3  2002-01-01 14:59:00.000 108.99999999999999
4  2002-01-01 15:17:00.000 18.000000000000004
5  2002-01-01 15:20:00.000 3.0
6  2002-01-01 18:39:00.000 199.0
7  2002-01-01 18:40:00.000 1.0
```

This was last published in August 2002

#### Have a question for an expert?

Get answers from a TechTarget expert on whatever's puzzling you.

You will be able to add details on the next page.

#### Start the conversation

Send me notifications when other members comment.

## SearchDataManagement

• ### GDPR data protection edicts make good data governance a must

The European Union's new GDPR law puts the onus on companies to ensure that their data governance and management practices enable...

• ### GDPR rules can spur broader steps to protect sensitive data

Companies need to make compliance with GDPR's requirements on managing personal data a priority, but they should also work to ...

• ### Data integrity protection spurs greater security spending

As hacking, ransomware and malware attacks mount, companies place big data protection and integrity among the primary reasons for...

• ### Cambridge Analytica-Facebook case shows need for ethical data mining

Ethical data collection practices are becoming even more important, as cases like Cambridge Analytica's misuse of Facebook data ...

• ### Rethinking analytics processes spurs enterprise innovation

By taking a fresh look at the makeup of their analytics organizations, enterprises can innovate their business models and take ...

• ### Diversified data sets for analytics deliver top results

Analytics teams should focus on data diversity to ensure that their projects deliver the most meaningful insights -- but they ...

## SearchSAP

• ### SAP indirect access debate tackled in new licensing model

SAP wants to resolve the indirect-access issue with a new, document-based licensing model. Analysts think customers will be happy...

• ### Pros and cons of SAP Cloud Platform integration tools

While SAP offerings are often best for cloud-to-cloud and cloud-to-ground integration, sometimes, it's better to look elsewhere. ...

• ### Supply chain risk assessment a major focus of SAP Ariba

SAP Ariba's Supplier Risk helps companies assess their suppliers in a number of risk categories, but building a responsible ...

## SearchSQLServer

• ### Why running SQL Server on Docker is no longer frowned upon

Microsoft now lets SQL Server databases run in Docker containers, a capability that depends on using volumes to store data in a ...

• ### What the Microsoft GDPR compliance toolkit offers for SQL Server

The set of GDPR compliance tools that Microsoft offers for SQL Server is designed to make it easier for users of the database ...

• ### How much do you know about the components of SQL Server?

From SQL Server Machine Learning Services to the SQL Server Operating System, there's a lot to know about SQL Server. Test your ...

## TheServerSide.com

• ### How JPA and Hibernate simplify data persistence

JPA is the Java standard for data persistence, especially for relational systems. Here, we explore how Hibernate and JPA work ...

• ### Let's talk bitcoin and building blockchain apps fast with Hyperledger

If you're thinking about building blockchain apps, you're probably looking for the right tools and technologies. Hyperledger ...

• ### The best web programming languages for development

Many technologies have emerged to facilitate browser-based development. Here, we look at those technologies in an effort to ...

## SearchDataCenter

• ### Guide to buying server performance monitoring software

Integration, storage and vendor support all affect whether a performance monitoring tool is right for an organization. Mull over ...

• ### How IBM's data science team quickens users' AI projects

In this Q&A, IBM's Seth Dobrin discusses the rising user interest in machine learning and AI projects and the help inexperienced ...

• ### IBM blockchain technology spotlights mainframes

IBM's blockchain offerings aim to ease enterprise IT concerns by combining Z system mainframe hardware with industry-specific ...

## SearchContentManagement

• ### How a digital transformation process helped curb reliance on paper

By moving on from paper, the North Carolina Court System and the Texas Animal Health Commission were able to accommodate ...

• ### Intelligent information management is ready for AI, blockchain

A panel discussion at AIIM 2018 looked at how AI, cloud and blockchain will disrupt the intelligent information management space.

• ### SharePoint 2019 on premises the talk of SharePoint Fest D.C.

This episode of the Pipeline podcast breaks down SharePoint users' concerns about data migration, on-premises version support, ...

## SearchHRSoftware

• ### Video interview platforms make headway against consumer tech

Some recruiters prefer the familiarity of popular video tools, like FaceTime and Skype, but they may be missing out on the rich ...

• ### Workday payroll system covers Minnesota healthcare network

A big physicians group affiliated with the University of Minnesota Medical School opted for a Workday cloud payroll system to ...

• ### Federal HR seeks corporate simplicity, says its new chief

Federal HR has a new reformer, Jeff Pon, the director of the U.S. Office of Personnel Management. He wants to modernize federal ...

Close