Given a composite index (country, city, created_at), which WHERE clause is most likely to use the index efficiently?

Problem Statement

Explanation

Composite B-trees are left-prefix. Predicates on leading columns enable seeks. Skipping the first column usually prevents efficient use. Adding a selective range on created_at after equality filters still works well.

Code Solution

SolutionRead Only

CREATE INDEX idx_loc_time ON places(country, city, created_at);

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Indexing Strategies & Access Paths

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Given a composite index (country, city, created_at), which WHERE clause is most likely to use the index efficiently?

Problem Statement

Explanation

Code Solution

Practice Sets

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Master Interviews Anywhere, Anytime

Given a composite index (country, city, created_at), which WHERE clause is most likely to use the index efficiently?

Problem Statement

Explanation

Code Solution

Practice Sets

Related Questions

Which SQL statement retrieves all columns and rows from a table named employees?

Which clause filters rows before aggregation and affects which rows are grouped?

What is the default sort order when ORDER BY is used without ASC or DESC?

Which construct is commonly used to paginate results in SQL engines like Postgres and MySQL?

Which predicate correctly checks for missing values in standard SQL?

More from SQL & Databases

Master Interviews
Anywhere, Anytime