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On Date Formats in DB2 – Part 2

Here is a follow-up question and answer based on my previous blog post: Q: My format does not fit into any of the formats listed in the DB2 manuals.

On Date Formats in DB2 – Part 1

From time to time I use the blog as a forum to answer questions I get via e-mail. Today, we address a popular theme – dealing with DB2 date data.

DB2 Date and Time Data

DB2 allows you to add and subtract DATE, TIME, and TIMESTAMP columns. In addition, you can add date and time durations to, or subtract them from, date and time columns.

Q+A: Locking

The question was: I want to perform a retry on an INSERT under DB2 Z/OS when I get a deadlock/timeout. -911 causes a rollback automatically.

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.

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.

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.

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.

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.

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.

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.

Returning Only Numeric Data

We want to examine CHAR data but return only those where the entire data consists only of numbers. For example, can we write a query like this?