Modify Stage - Handling NULLs

For handling the NULL value in columns we can use modify functions in DataStage instead of Transformer. Rather, I'll always prefer a transformer to avoid unnecessary effort which we put to setting up modify stage. But sometime to tune the job over performance we have to do that ;-)

The below Function Specification we have to use to Handle NULL --

Datastage Coding Checklist

1. Ensure that the null handling properties are taken care for all the nullable fields. Do not set the null field value to some value which may be present in the source.
2. Ensure that all the character fields are trimmed before any processing. Normally extra spaces in the data may lead to some errors like lookup mismatch which are hard to detect.
3. Always save the metadata (for source, target or lookup definitions) in the repository to ensure re usability and consistency.

ETL Job Design Standards - 2

Part 1 --> ETL Job Design Standards - 1

Parameter Management Standards

This section defines standards to manage job parameters across environments. Jobs should use parameters liberally to avoid hard coding as much as possible. Some categories of parameters include: 

• Environmental parameters, such as directory names, file names, etc.
• Database connection parameters
• Notification email addresses
• Processing options, such as degree of parallelism

ETL Job Design Standards - 1

When using an off-the-shelf ETL tool, principles for software development do not change: we want our code to be reusable, robust, flexible, and manageable. To assist in the development, a set of best practices should be created for the implementation to follow. Failure to implement these practices usually result in problems further down the track, such as a higher cost of future development, increased time spent on administration tasks, and problems with reliability.

Although these standards are listed as taking place in ETL Physical Design, it is ideal that they be done before the prototype if possible. Once they are established once, they should be able to be re-used for future increments and only need to be reviewed. 

Listed below are some standard best practice categories that should be identified on a typical project.