2 Matching Annotations
- Jan 2023
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onlinelearning.berkeley.edu onlinelearning.berkeley.edu
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An inner join is best thought of as an exclusive join because the result set includes only rows where matches were found in both tables (unmatched rows are excluded from the results)
TLDR inner join = exclusive to matches in both tables * Any row from the key table which has a value that is omitted from the key column (Horse table has key columns of sire_id and dam_id) is exlcuded from the final result. So if horse_id_x has a null value for its sire or dam id, then any information about the row corresponding to horse_id_X is entirely ommitted from the final result of the joined table.
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We used an inner join in the previous query, so non-matched rows are discarded
inner joins I think match two rows based on a common column
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