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Welcome to Datavail's Blog, where you can read the latest insights, tips and opinions of our experts on all things data and technology.

Category: Db2

Consider Table Expressions to Improve Performance

Table expressions are frequently overlooked as a potential solution for resolving problems using only SQL. Learn more in this post.

Craig Mullins | December 23, 2015

Database Performance and Row Size for DB2

“Does the number of columns or size of the row matter in terms of performance?” Let’s explore this question in further detail.

Craig Mullins | December 18, 2015

Q+A: Nulls and DASD

Let’s say I have a table A which has 500 columns. Out of those 500 columns only 5 columns have been defined as not nullable and the rest have been defined as NULLS allowed.

Craig Mullins | December 14, 2015

VARCHAR versus Compression

This blog will compare the use of VARCHAR to DB2 compression when you are building your DB2 databases. Visit to learn more.

Craig Mullins | October 27, 2015

Evaluating DB2 Tool Vendors

You should really do the investigative work required to find out the real level of support for DB2 V11 that is in the GA version of the tool. Read more.

Craig Mullins | September 1, 2015

Adding Column Names to an Unload File

Are any of the DB2 unload utilities able to include the column names in the same file as the unload output data? Read on to discover the answer.

Craig Mullins | August 19, 2015

Advice on Using Variable Character Columns in DB2

One of the long-standing, troubling questions in DB2-land is when to use VARCHAR versus CHAR.

Craig Mullins | August 4, 2015

There’s a Better Way to Use Your DBAs

When an organization doesn’t have 24×7 support, the senior database administrator is typically forced to do low-level work and is placed on-call for emergencies. She becomes bogged down in “administrivia” and is unable to operate effectively.

Robin Caputo | July 15, 2015

Using Nulls in DB2

Nulls are clearly one of the most misunderstood features of DB2. Here are some examples, tips & guidelines from Craig Mullins to demystify the use of nulls.

Craig Mullins | April 6, 2015