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Inner Join vs Outer Join
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Inner Join vs Outer Join

EasySQL · PostgreSQL

Problem

Explain the difference between inner join and outer join in SQL.

Use the provided users and orders tables to demonstrate the difference with matching and unmatched records. Show the results from both join types in one result set.

Output

  1. Columns: join_type, user_id, user_name, order_id, amount
  2. Include matching rows for both join types and unmatched rows for the outer join
  3. Sort by join type, then user ID and order ID

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
user_nameVARCHAR(100)User's display name
orders
ColumnTypeDescription
order_idPKINTUnique order identifier
customer_idINTUser who placed the order
amountNUMERIC(10,2)Order amount
Tablesusersorders
Interviewer

Your question is Inner Join vs Outer Join. Start with the requirements and the two tables in the Question tab.

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CodePostgreSQL
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