Prepare for and practice interview questions from Square across topics like SQL, Python, Product Metrics and more.

Square Interview Questions

Python

Machine Learning

Product Metrics

A/B Testing

Analytics

Statistics

Probability

Algorithms

Square Interview Guides

Let’s say at Netflix we offer a subscription where customers can enroll for a 30-day free trial. After 30 days, customers will be automatically charged based on the package selected.

Let’s say we want to measure the success of acquiring new users through the free trial.

How can we measure acquisition success and what metrics can we use to measure the success of the free trial?

Let’s say we want to measure the effectiveness of Netflix’s 30-day free trial plan.

What is NOT a metric we would use?

Let's say we want to measure the effectiveness of Netflix's 30-day free trial plan.

What is NOT a metric we would use?

Netflix Retention

You’re tasked with designing a database system for Swipe Inc., a company that manages payments for software developers. Swipe manages a set of APIs so developers can abstract payment processes for their web service and transfer control over to Swipe’s APIs to manage payment security and finance handling (contacting credit card providers, etc.)

Your database system should store a collection of API keys with their attributes, as shown in the example below:

<pre tabindex="0" class="chroma"><code>{
 &#34;API_key&#34;:{
 &#34;Transaction_list&#34;:{
 &#34;User_ID&#34;:{
 &#34;Name&#34;:{
 &#34;f_name&#34;: 
 &#34;l_name&#34;: 
 }
 &#34;Card_Details&#34;:{
 &#34;Bank&#34;:
 &#34;Card_No&#34;:
 &#34;Expiry&#34;:
 &#34;CV&#34;:
 } 
 }
 }
 &#34;Curr_balance&#34;:
 }
}
</code></pre>

What are the functional and non-functional requirements for this database?

Determine the requirements for designing a database system to store payment APIs

Swipe Payment API

Write a SQL query to create a histogram of the number of comments per user in the month of January 2020.

Note: Assume bin buckets class intervals of one.

Note: Comments that were created outside of January 2020 should be counted in a “0” bucket

Example:

Input:

<code>users</code> table

<table>
<thead>
<tr>
<th>Columns</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>name</code></td>
<td>VARCHAR</td>
</tr>

<tr>
<td><code>created_at</code></td>
<td>DATETIME</td>
</tr>

<tr>
<td><code>neighborhood_id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>mail</code></td>
<td>VARCHAR</td>
</tr>
</tbody>
</table>
<code>comments</code> table

<table>
<thead>
<tr>
<th>Columns</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>user_id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>body</code></td>
<td>VARCHAR</td>
</tr>

<tr>
<td><code>created_at</code></td>
<td>DATETIME</td>
</tr>
</tbody>
</table>
Output:

<table>
<thead>
<tr>
<th>Column</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>comment_count</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>frequency</code></td>
<td>INTEGER</td>
</tr>
</tbody>
</table>

Write a SQL query to create a histogram of the number of comments per user in the month of January 2020.

Square Interview Questions

Square Interview Guides

Square Interview Questions

This feature requires a user account

Square Salaries by Position