Explorer
SQL

Find users whose age is between 25 and 35 (inclusive).

Problem Statement

<p>Find <code>users</code> whose age is between 25 and 35 (inclusive).</p>

Examples

Input: users table: +----+---------+-----+ | id | name | age | +----+---------+-----+ | 1 | Alice | 20 | | 2 | Bob | 25 | | 3 | Charlie | 30 | | 4 | Dana | 40 | +----+---------+-----+

Output: +----+---------+-----+ | id | name | age | +----+---------+-----+ | 2 | Bob | 25 | | 3 | Charlie | 30 | +----+---------+-----+

Explanation: Only records matching the specified criteria are returned in the final result.

Complexity

Time Complexity: -

Space Complexity: -

Hints

šŸ’” Hint 1: Identify the filtering conditions needed to isolate the target rows from the table. šŸ’” Hint 2: Use appropriate operators: = for exact matches, LIKE for wildcard patterns, IN for sets, or BETWEEN for numeric/date ranges. šŸ’” Hint 3: Combine filters with AND/OR if multiple conditions exist: SELECT <cols> FROM <table> WHERE <condition>;

Editorial & Approach

Problem Overview & Intuition

To solve "BETWEEN Range Filter", we query the relational database engine using declarative SQL. The goal is to find users whose age is between 25 and 35 (inclusive). By formulating an optimal execution plan with appropriate projection and filtering, the database engine executes the query with minimal overhead.

Step-by-Step Approach

  1. Analyze Schema: Identify the target tables, necessary foreign keys, and expected output columns.
  2. Construct Filtering & Logic: Apply WHERE filtering to isolate the requested data.
  3. Format & Order: Ensure columns match the expected project schema in order.

Optimal Implementation (SQL)

SELECT * FROM users WHERE age BETWEEN 25 AND 35;

Complexity Analysis

Time Complexity O(N) full table scan or O(log N) if filtered column is indexed.
Space Complexity O(K) where K is the number of filtered rows returned.

Key Considerations & Edge Cases

  • Empty Tables: The query executes safely returning zero rows without syntax error.
  • NULL Values: Columns containing NULL values are properly handled by standard ANSI SQL semantics.
  • Case Sensitivity: String comparisons and keywords adhere to PostgreSQL/standard SQL rules.

BETWEEN Range Filter

Easy

Find users whose age is between 25 and 35 (inclusive).

Example Scenarios
1Example 1
Input:
users table
idnameage
1Alice20
2Bob25
3Charlie30
4Dana40
Output:
idnameage
2Bob25
3Charlie30
Explanation:

Only records matching the specified criteria are returned in the final result.

SQL Editor
Loading Editor...
Query Results

Run a query to see results here.