Errors Happen
Metric values shouldn't
vary across reports, but
they do. Find out why.
Common ways errors sneak in:
  • Code Duplication:  SQL code from
    existing reports is "cloned" to new
    ones, but subsequent changes
    aren't applied to every copy.
  • No Source Control:  Without some
    form of versioning or change logs,
    your code base can't stay current.
  • Reference Data:  Sometimes this
    is updated manually in the source
    system, but not in the SQL code
    of every report that uses it.
  • SQL Gone Wrong:  Code goes live
    without proper testing (happens
    more often than you'd think).
Related Info
How to Fix
Those Reports

There are many causes of erratic results, such as SQL cloning, weak source control, frequent break-fix work, and untested code.

One way to keep reports consistent is to build a Data Mart ETL system that runs overnight and sets up results in static tables.

To learn more about Data Mart ETL, read my post:
Data Mart ETL Basics

Upgrade Your
SQL Skills

No matter how your reports and analyses are implemented, they're only as good as the SQL behind them.

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