Glossary · Phase 3 · Machine learning
Left join
Ways to combine two tables on a shared key. A left join keeps every row of the first table; an inner join keeps only rows found in both.
Try it now
Pick the join from what should happen to rows without a match. If you can't say, look at the unmatched rows first with indicator=True.
Learn it properly
Combining tables with merge · Join on keys safely, stack tables, and divide by the right denominator. About 40 minutes.
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