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Onumaku Chibuike Victory
Onumaku Chibuike Victory

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SQL JOINS

Hey, Data Analysts! Every Data Analyst needs to master SQL JOINS. Need help? I've got you! Here's a breakdown of SQL joins and their uses: --------------------------------------------------------------------------
➡️ Inner Join: The meeting point of two tables based on a shared key. It returns rows with a match in both tables, effectively the 'intersection' in a Venn diagram of datasets.
➡️ Left Join (Left Outer Join): This join fetches all records from the 'left' table and the matched records from the 'right' table. If there's no match, the result is NULL on the right side. ➡️ Right Join (Right Outer Join): It's the opposite of a Left Join. All records from the 'right' table and the matched records from the 'left' table are returned. No match? You'll get NULL on the left.
➡️ Full Outer Join: Imagine combining the powers of both Left and Right Joins. This join returns all records when a match is in the left or right table. Unmatched records from both sides will appear, with NULLs filling the gaps.
➡️ Left Anti-Join: This lesser-known join fetches rows from the left table with no corresponding match in the right table. It's like saying, "Tell me what's exclusive to the left table."
➡️ Right Anti-Join: The mirror image of the Left Anti-Join. It retrieves rows from the right table that find no echo in the left table.

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Onumaku Chibuike Victory

Master SQL Joins