Pandas SQL Query: Select distinct department id from employees file

Pandas HR database Queries: Exercise-4 with Solution

Write a Pandas program to select distinct department id from employees file.

DEPARTMENTS.csv

Sample Solution :

Python Code :

import pandas as pd
employees = pd.read_csv(r"EMPLOYEES.csv")
departments = pd.read_csv(r"DEPARTMENTS.csv")
job_history = pd.read_csv(r"JOB_HISTORY.csv")
jobs = pd.read_csv(r"JOBS.csv")
countries = pd.read_csv(r"COUNTRIES.csv")
regions = pd.read_csv(r"REGIONS.csv")
locations = pd.read_csv(r"LOCATIONS.csv")
print("Distinct department_id:")
print(employees.department_id.unique())

Sample Output:

 Distinct department_id:
[ 90.  60. 100.  30.  50.  80.  nan  10.  20.  40.  70. 110.]

Equivalent SQL Syntax:

SELECT DISTINCT department_id FROM EMPLOYEES;

Click to view the table contain:

Employees Table

Departments Table

Countries Table

Job_History Table

Jobs Table

Locations Table

Regions Table

Python Code Editor:

Structure of HR database :

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