Full Outer Joins Step by Step

A compact FULL OUTER JOIN book for readers who need exact finite join behavior: left/right inputs, candidate key matches, matched output rows, left-only rows padded with right NULLs, right-only rows padded with left NULLs, duplicate-key match multiplication, output row classification, and guarded expected facts.

Full Outer Joins

Left and Right Tables
Candidate Key Matches
Matched Output Rows
Left-Only Rows Get Right NULLs
Right-Only Rows Get Left NULLs
Duplicate Keys Multiply Matches
Output Row Classification
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