### Educational Exercise: Understanding DataFrame Merging in Pandas**Question:**What is the output of the following command?```pythonpd.merge(dataframe_employees, dataframe_sales, on='employee_id')```**Options:**- ⦿ inner merge the employee dataframe with the sales dataframe- ⦿ outer merge the employee dataframe with the sales dataframe- ⦿ left merge the employee dataframe with the sales dataframe- ⦿ right merge the employee dataframe with the sales dataframe### Explanation:In this question, you are required to identify the type of merge performed by the `pd.merge()` function in the given Python command. The function merges two dataframes, `dataframe_employees` and `dataframe_sales`, based on the common column `employee_id`.#### Definition of Merge Types:1. **Inner Merge:** - Only common rows across both dataframes based on the condition (here, `employee_id`) are retained. - Example: `pd.merge(dataframe_employees, dataframe_sales, on='employee_id', how='inner')`2. **Outer Merge:** - All rows from both dataframes are retained. Non-matching rows will result in `NaN` in the places where no match was found. - Example: `pd.merge(dataframe_employees, dataframe_sales, on='employee_id', how='outer')`3. **Left Merge:** - All rows from the left dataframe (`dataframe_employees`) are retained, and matching rows from the right dataframe (`dataframe_sales`) are included. - Example: `pd.merge(dataframe_employees, dataframe_sales, on='employee_id', how='left')`4. **Right Merge:** - All rows from the right dataframe (`dataframe_sales`) are retained, and matching rows from the left dataframe (`dataframe_employees`) are included. - Example: `pd.merge(dataframe_employees, dataframe_sales, on='employee_id', how='right')`Since the given command does not specify the type of merge and `pd.merge()` by default performs an inner merge, the correct answer is:- **Option 1:** inner merge the employee dataframe with the sales dataframe.

What is the output of the following command: pd.merge(dataframe_employees, dataframe_sales, on='employee_id') inner merge the employee dataframe with the sales dataframe outer merge the employee dataframe with the sales dataframe left merge the employee dataframe with the sales dataframe right merge the employee dataframe with the sales dataframe

What is the output of the following command: pd.merge(dataframe_employees, dataframe_sales, on='employee_id') inner merge the employee dataframe with the sales dataframe outer merge the employee dataframe with the sales dataframe left merge the employee dataframe with the sales dataframe right merge the employee dataframe with the sales dataframe

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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