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Start from a question
A model has no edge until a question gives it one. Model only what the question touches, and name who owns each meaning first.
Topics › Analytics engineering › In the weeds of data crafting
What makes it the same one: identity is a decision, written down
Aisha arrives under three keys, and another Aisha looks just like her. Profile the sources with a query behind every claim, qualify each key, match by rules most trusted first, let a person decide what rules can't, and hash every key the same way everywhere.
Builds on Start from a question
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 learner under three keys, and a look-alike. Now match them 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.
- Profile first
analyses/profiling/profile_null_keys.sqlanalyses/profiling/profile_shared_emails.sqlanalyses/profiling/profile_orphans.sql - Key sets
seeds/reference/shared/key_sets.csvmacros/shared/keys.sqlmodels/staging/short_courses/stg_short_courses__learners.sql - Rules, most trusted first
models/intermediate/student/int_learner_key_candidates.sqlmodels/intermediate/student/int_learner_keys_matched.sqlmodels/core/student/_student__conceptual.yml - Keep them apart
seeds/reference/student/learner_identity_decisions.csvmodels/intermediate/student/int_learner_key_candidates.sqltests/rules/keys_decided_different_stay_apart.sql - The same hash everywhere
macros/shared/keys.sql - Codes, too
seeds/reference/student/status_map.csvseeds/reference/student/_student__seeds.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
Film 3 of 10.
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One row of what, and when
Twelve on census day, nine today: both right. Say what one row is and which day it describes, before any SQL, and test both.