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What SQL JOIN Does
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What SQL JOIN Does

EasySQL · PostgreSQL

Problem

What does a SQL JOIN do?

Write a PostgreSQL query that demonstrates this by returning customers who have a matching account record. Include only matched customer-account pairs.

Output

  1. One row per matched customer-account pair
  2. Columns: customer_name, account_type
  3. Sort by customer_name, then account_type

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer's full name
accounts
ColumnTypeDescription
account_idPKINTUnique account identifier
customer_idINTCustomer associated with the account
account_typeVARCHAR(50)Type of bank account
Tablescustomersaccounts
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Your question is What SQL JOIN Does. Start with the requirements and the two tables in the Question tab.

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