MediumNo. 1907

Count Salary Categories — LeetCode 1907 Python Solution

Topics
Database
Reading time
5 min

Table schema

SQLTable schema
Table: Accounts +-------------+------+ | Column Name | Type | +-------------+------+ | account_id | int | | income | int | +-------------+------+ account_id is the primary key (column with unique values) for this table. Each row contains information about the monthly income for one bank account.

Example

SQLExample
+-------------+------+
| Column Name | Type |
+-------------+------+
| account_id  | int  |
| income      | int  |
+-------------+------+
account_id is the primary key (column with unique values) for this table.
Each row contains information about the monthly income for one bank account.

Python solution

PythonSolution
import duckdb
import pandas as pd

def solution(accounts: pd.DataFrame) -> pd.DataFrame:
    con = duckdb.connect()
    con.register("Accounts", accounts)
    return con.execute("""WITH
    S AS (
        SELECT 'Low Salary' AS category
        UNION
        SELECT 'Average Salary'
        UNION
        SELECT 'High Salary'
    ),
    T AS (
        SELECT
            CASE
                WHEN income < 20000 THEN "Low Salary"
                WHEN income > 50000 THEN 'High Salary'
                ELSE 'Average Salary'
            END AS category,
            COUNT(1) AS accounts_count
        FROM Accounts
        GROUP BY 1
    )
SELECT category, IFNULL(accounts_count, 0) AS accounts_count
FROM
    S
    LEFT JOIN T USING (category);""").df()

Complexity

Time
O(n log n)(typical)
Space · auxiliary
O(n)

Related problems

Related problems
No.ProblemDifficulty
0175Combine Two TablesEasy
0176Second Highest SalaryMedium
0177Nth Highest SalaryMedium
0178Rank ScoresMedium
0180Consecutive NumbersMedium
0181Employees Earning More Than Their ManagersEasy

Frequently asked questions

How hard is LeetCode 1907. Count Salary Categories?

LeetCode 1907. Count Salary Categories is rated Medium on LeetCode.

What topics does LeetCode 1907. Count Salary Categories cover?

LeetCode 1907. Count Salary Categories is tagged Database on LeetCode.

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