Index the Account Order Lookup
Create idx_orders_account_status on orders(account_id, status).
- Composite indexes
- Index design
Exercise brief
Understand the request
Database reliability The common support lookup filters orders by account_id and then status.
Order support repeatedly searches by account and status as the order table grows.
Return
- Create the named composite index with columns in lookup order.
Constraints
- Use the exact index name.
- Place account_id before status.
Data you will use
Review the relevant tables before deciding how to join, filter, or aggregate them.
orders
account_idINTEGERstatusVARCHAR(20)
Hints, when you need them
Open one clue at a time so you still do the reasoning.
Hint 1
A composite index can support filters that begin with its leading column.
Hint 2
Use CREATE INDEX with the exact name and list account_id before status.
Hint 3
CREATE INDEX idx_orders_account_status ON orders (account_id, status);
Verified SQL answer
Attempt the problem first, then compare structure and reasoning—not just syntax.
Reveal solution and explanation
CREATE INDEX idx_orders_account_status
ON orders (account_id, status);Why this works
The index order matches the stated access pattern and establishes a concrete performance object that can be inspected in the catalog.
Success check
The database catalog contains idx_orders_account_status on the orders table.
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