Tag
#pandas
2 articles
TutorialThe Practical Data Analyst · Careers
Five Date Traps That Move Money Between Months: I Measured Each One
Five controlled date experiments on a tiny orders table: a BETWEEN filter cut March from $420 to $170, a timezone moved $70 into February, and SQLite and pandas disagreed by three days on one month of arithmetic.
Ibrahim Denis Fofanah·Oct 21, 2026·10 min
TutorialCareers & Skills · Tutorial
Most Analytics Bugs Are Data Bugs. Five Checks That Catch Them Before the Meeting.
Five validation checks every analyst should run before trusting a table: duplicates, NULL key columns, out-of-range values, cross-field arithmetic, orphan references. Tested on a 2,010-row orders table with 50 planted defects; the checks flagged 51 rows, and the misses are as instructive as the catches.
Ibrahim Denis Fofanah·Oct 11, 2026·8 min