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Inner Join With Missing Values
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Inner Join With Missing Values

MediumSQL · PostgreSQL

Problem

Given two tables, write a Python script to perform an inner join and handle missing values.

Use the provided accounts and account_attributes tables. Return only records with matching account IDs, replacing missing output values with clear default labels.

Output

  1. One row per matching account ID
  2. Columns: account_id, account_name, segment, contact_email
  3. Replace missing names, segments, and email addresses with Unnamed account, Unknown, and Not provided
  4. Order by account_id ascending

Schema

accounts
ColumnTypeDescription
account_idPKINTUnique account identifier
account_nameVARCHAR(100)Display name of the account
account_attributes
ColumnTypeDescription
account_idPKINTAccount identifier associated with the attributes
segmentVARCHAR(50)Account segment
contact_emailVARCHAR(150)Primary contact email address
Tablesaccountsaccount_attributes
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