Optimize Queries with a Partial Index on Active Orders

Creating a Partial Index in PostgreSQL

Write a PostgreSQL query to create a partial index that only covers rows meeting a specific condition.

Solution:

-- Specify the action to create a partial index.
CREATE INDEX idx_orders_active 
-- Define the target table and column for the index.
ON Orders(order_date) 
-- Add a condition to limit the index to rows with active status.
WHERE status = 'active';

Explanation:

• Purpose of the Query:
• To index only a subset of rows (e.g., active orders), thereby saving space and improving performance for targeted queries.
• Key Components:
• WHERE status = 'active' : Limits the index to rows meeting the condition.
• idx_orders_active and ON Orders(order_date) : Define the index name and target column.

Notes:

• Partial indexes are ideal for large tables where only a portion of the data is frequently queried.
• They reduce index size and improve maintenance efficiency.

For more Practice: Solve these Related Problems:

• Write a PostgreSQL query to create a partial index on the "order_date" column for orders with status 'completed' in the "Orders" table.
• Write a PostgreSQL query to create a partial index on the "active" column in the "Users" table where active is true.
• Write a PostgreSQL query to create a partial index on the "price" column in the "Products" table where price is above 100.
• Write a PostgreSQL query to create a partial index on the "last_login" column in the "Customers" table for logins within the past 30 days.

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