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

# Birthdays in the next two weeks

I am making a data driven site and want an admin page to display a list of people whose birthdays are in the next...

14 days based on data from a MySQL database. How would I devise the SQL query to take in the current date and show me the birthdays from the database who are on or 14 days after the current date?

Thanks for mentioning that it's MySQL. That makes a big difference, because date functions are where database vendors stray the furthest from the SQL standard. Sometimes that's a good thing, though, and I really like MySQL's diverse and flexible date functions.

The part about this problem that's the toughest to figure out is what to do about year boundaries. You get into difficulty if you start by reconstructing the person's birthday this year --

```select DATE_FORMAT(CURRENT_DATE,'%Y')
+ DATE_FORMAT(birthdate,'-%m-%d')```

What if today is December 24 and the birthday is January 5? That's certainly within 14 days, but suddenly the comparison is not so straight-forward -- maybe you have to use the person's birthday next year, not this year, and do you subtract it from CURRENT_DATE or subtract CURRENT_DATE from the birthday?

Here's a better approach. My age, considered as an integer, does not go up until my next birthday is reached. If I'm 39 today, and in two weeks I'm 40, then my birthday must have occurred somewhere within those 14 days. Never mind whether we crossed a year boundary. All we need is a convenient formula for age in years. The MySQL docs give a splendid example --

To determine how many years old each of your pets is, compute the difference in the year part of the current date and the birth date, then subtract one if the current date occurs earlier in the calendar year than the birth date. The following query shows, for each pet, the birth date, the current date, and the age in years.

```select ( YEAR(CURRENT_DATE) - YEAR(birth) )
- ( RIGHT(CURRENT_DATE,5) < RIGHT(birth,5) )
as age```

Here, YEAR() pulls out the year part of a date and RIGHT() pulls off the rightmost five characters that represent the MM-DD (calendar year) part of the date. The part of the expression that compares the MM-DD values evaluates to 1 or 0, which adjusts the year difference down a year if CURRENT_DATE occurs earlier in the year than birth.

Now all we have to do is compare the person's age in 14 days with the age today and Bob's your uncle --

```select lastname, birthdate
from yourtable
where ( YEAR(DATE_ADD(CURRENT_DATE, INTERVAL 14 DAYS))
- YEAR(birthdate) )
- ( RIGHT(DATE_ADD(CURRENT_DATE, INTERVAL 14 DAYS),5)
< RIGHT(birthdate,5) )
> ( YEAR(CURRENT_DATE)
- YEAR(birthdate) )
- ( RIGHT(CURRENT_DATE,5)
< RIGHT(birthdate,5) ) ```

This problem is also discussed on pages 74-76 of Joe Celko's SQL for Smarties (ISBN 1-55860-323-9).

#### For More Information

• The Best SQL Web Links: tips, tutorials, scripts, and more.
• Have an SQL tip to offer your fellow DBAs and developers? The best tips submitted will receive a cool prize. Submit your tip today!
• Ask your technical SQL questions -- or help out your peers by answering them -- in our live discussion forums.
• Ask the Experts yourself: Our SQL, database design, Oracle, SQL Server, DB2, metadata, object-oriented and data warehousing gurus are waiting to answer your toughest questions.

This was last published in March 2002

## Content

Find more PRO+ content and other member only offers, here.

#### Have a question for an expert?

Please add a title for your question

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

• ### Connectedness is king, as Neo4j graph database ports to Spark

The Neo4j graph database emphasizes easy relationship mapping for diverse data points. Now, its related Cypher query language is ...

• ### NewSQL databases rise anew -- MemSQL, Spanner among contenders

The NewSQL database was almost hidden when Hadoop and NoSQL arose. Now, as more big data teams move toward production uses, ...

• ### Good data quality for analytics becomes an IT imperative

High-quality data is a must for analytics applications. That's driving more demand for data quality tools, but quality ...

## SearchBusinessAnalytics

• ### Tableau targets data preparation software with Project Maestro

As Tableau and other high-level applications look to automate more functionality, stand-alone data preparation tools have to ...

• ### AI components make tools more than the sum of their parts

AI applications, rather than being one monolithic tool, are built around a diverse collection of tools and techniques that ...

• ### At AT&T, CDO responsibilities to include all things AI

At most companies, the chief data officer role tends to focus on data governance and management issues, but at AT&T, AI is set to...

## SearchSAP

• ### Responsible sourcing can be good for business

A company's reputation and bottom line can be damaged if its suppliers engage in harmful practices. Responsible sourcing and risk...

• ### SAP TechEd 2017 focuses on next-gen development tools

At SAP TechEd 2017, SAP rolled out some new developer tools that are intended to extend the SAP platform and drive development of...

• ### SAP Analytics Cloud helps paper-maker tell a good business story

SAP Analytics Cloud software is helping paper manufacturer Pratt Industries tell the story of monthly forecasts more accurately, ...

## SearchSQLServer

• ### Microsoft technology refresh touches SQL Server, integration tooling

Microsoft is at work on a delicate technology refresh affecting database tuning and architecture, as well as data integration and...

• ### Microsoft boosts SQL Server machine learning services

Python and R are among the tools in the SQL Server machine learning toolkit. Native T-SQL scoring is also on the agenda, as ...

• ### Power BI updates drive Microsoft's latest hybrid cloud efforts

At PASS Summit 2017, Microsoft Azure's strides were measured in steps. These include Power BI updates that bring cloud reporting ...

## TheServerSide.com

• ### Can DevOps problems actually cause projects to fail?

DevOps isn't perfect. There are times when DevOps problems can overwhelm the potential benefits. So, why do some DevOps projects ...

• ### Owning the Java Platform is more of a burden or a blessing

Oracle became stewards of the Java platform as a by-product of their acquisition of Sun Microsystems. But looking back, it seems ...

• ### Migrations to Oracle's Java SE 9 platform may be delayed

Oracle did a great job getting Java SE 9 released earlier this year, but modularity and various smaller updates may not be enough...

## SearchDataCenter

• ### Data center GPU use on the rise thanks to AI, big data

GPU vendors have added new devices and cards for data center servers, as data demanding workloads infiltrated the data center and...

• ### SD-WAN benefits branch networks with simplicity, automation

Traditional branch networks haven't adapted well to new technologies. But a mature SD-WAN market can bring distributed networks ...

• ### Composable infrastructure creates new path to SDDC nirvana

Shiny new products like composable infrastructure and on-premises cloud platforms could offer a way to achieve software-defined ...

## SearchContentManagement

• ### Q&A: New CEO bets on open source future for Acquia CMS

The Acquia CMS took the Red Hat model to content management by commercializing open source Drupal. What's next? We ask co-founder...

• ### CMS analytics arms businesses with a strategic planning edge

Content analytics for CMSes mines business value from free text in data lakes, so it's time to go prospecting for gold with this ...

• ### Enterprise content management systems boost intelligence

Content analytics moves beyond the tried-and-true web analytics style of insights, adding natural language processing and images ...

## SearchFinancialApplications

• ### Finance IT case study: Reporting secrets of Derek Rose

CEO Sacha Rose says specialist reporting tools have saved the company thousands by avoiding unnecessary mistakes.

• ### WestJet turns to gamification to help its Oracle ERP users soar

WestJet's initial gamification project focuses on expense reporting.

• ### The Transformation of HR is Underway

HR is being transformed while we watch.

Close