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Keys and Transactions

As you may already know, databases use tables to organize information. Each table consists of a number of rows, each corresponding to a single database record. So, how do databases keep all of these records straight? It's through the use of keys.

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Mike's Databases Blog

Access to SQL Server Replication

Tuesday August 26, 2008
In a recent forum message, ICCLEARLY wrote:

"We are looking for a way to set up replication between several remote MS Access databases and a central MS SQL Server database. Can anyone help with this?"

Interested in solutions to the same problem? Have some advice? Join the discussion in our forum!

Oracle 11g Certification Programs

Sunday August 24, 2008
In this article, we'll take a brief look at the Database Administrator track and the three possible certifications you can earn on your way to Master status. Our next article will examine the Application Developer track. As with most vendor-specific certifications, the OCP program provides version-specific examinations. Currently, there are three active certification programs: Oracle 9i, Oracle 10g and Oracle 11g. I'd strongly encourage you to certify on the most recent version of Oracle in order to maintain your credential as long as possible.

Read the full article: Oracle 11g Certification Programs

SQL Server 2008 is Here!

Thursday August 21, 2008
Earlier this month, Microsoft announced the release to manufacturing (RTM) of SQL Server 2008. You can download a 180-day evaluation edition of SQL Server 2008 from the Microsoft website and get started playing with it today. In their announcement, Microsoft confirmed their earlier statements that the pricing for SQL Server 2008 will remain the same as that put in place for SQL Server 2005.

Are you going to adopt 2008 immediately? Waiting a few months to see what's going to be included in Service Pack 1? Skipping this version entirely? Join the discussion in the About Databases forum!

Help with the MAX() function

Tuesday August 19, 2008
In a recent forum posting, aoneistheman wrote:

"I'm a SQL newbie, and am creating this crazy view of other views. I need help using the MAX() function.

I have a table that holds a wage id, a person id, salary, and salary start date. A person that gets a raise, gets a new record with a different salary, and a new wage id. I need the record with the latest date. So I do a simple select:

SELECT person_id, MAX(sal_str_dt) as Salary_Strt_Date
FROM Salaries
GROUP BY person_id

Results:

id Salary_Strt_Date
15 12312008
144 07011996

I also need the salary amount along with those two columns. Yet, SQL will not allow me to just add salary in the select statement, unless I give it the following MAX(Salary). I don't want the max salary though, as it may not be in the same record as the max date, and would mess up my results. Any Idea as to how I can get the salary that corresponds with the latest date, and still group by the person_id?"

Can you help? Interested in solutions to the same problem? Visit our forum and join the discussion!

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