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What makes it the same one
One learner, three keys, and a look-alike. Rules match most of them; a person decides the rest, and the decision becomes data and a test.
Topics › Analytics engineering › In the weeds of data crafting
One row of what, and when: twelve and nine, both right
One question gives twelve on census day and nine today, and both are right. Before any SQL, say in one sentence what one row is and which day it describes, test it as a key, and join every versioned thing at that day.
Builds on What makes it the same one
Watch the film
Press Play, or pick a chapter. Turn on Pause and think to stop for one question at the end of chapters.
Download the videoCaption filesRead the script
Where next?
You've seen one question give two right answers. Now declare the grain and the day yourself.
See it in the project
Every card in the film shows a real file from the example dbt project. Open the ones each chapter shows, on GitHub, or run the whole project yourself.
- One sentence
seeds/expected/planning/census_report.csvmodels/marts/planning/_planning__models.ymldocs/conventions.md - Fan-out
analyses/design/fan_out_without_point_in_time.sql - Every version kept
models/_shared/_shared__columns.mdmodels/core/student/_core_student__models.yml - As it was, as it is
macros/shared/time.sqlmodels/marts/planning/mart_planning__near_award.sqlmodels/marts/planning/_planning__decisions.ymlmodels/marts/wallet/_wallet__decisions.yml - One timeline
models/intermediate/student/int_learner_timeline.sql - Late news
analyses/profiling/profile_late_changes.sqlmodels/intermediate/student/int_learner_timeline.sqlmodels/core/student/_core_student__models.yml
Think it through
The four Pause and think questions, for a class or a team. Open one to see the answer.
In the series: In the weeds of data crafting
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Promises and proofs
Every gap gets a decision. Promise it in a contract; prove it with a test, written before the code it checks.