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Let’s say we have a table with an <code>id</code> and <code>name</code> fields. The table holds over 100 million rows and we want to sample a random row in the table without throttling the database.

Write a query to randomly sample a row from this table.

Input:

<code>big_table</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>
</tbody>
</table>

Write a query to randomly sample a row from a big table.

Random SQL Sample

Let’s say that your company is running a standard control and variant AB test on a feature to increase conversion rates on the landing page. The PM checks the results and finds a .04 p-value.

How would you assess the validity of the result?

Experiment Validity

You are testing hundreds of hypotheses with many t-tests. What considerations should be made?

What is a key disadvantage of the F-test when compared to multiple t-tests?

What is a key disadvantage of the F-test when compared to multiple t-tests?

Hundreds of Hypotheses

You are testing hundreds of hypotheses with many t-tests. What considerations should be made?

Tek Leaders Inc Salaries by Position

Role: DBT (Core/ Cloud) DeveloperLocation: Remote Please find the revised JD Senior DBT Developer. Please evaluate the resume based on below highlighted skills. <ul><li>Client looking for Senior/ Lead DBT Developer. </li><li>Good AWS experience.</li><li>Should have some DBT Admin experience.</li></ul> Senior DBT developer:Technical Skills:DBT Proficiency: <ul><li>model development: </li><li>Experience in creating complex DBT models including incremental models, snapshots and documentation</li><li>Ability to write and maintain DBT macros for reusable code</li><li>Testing and documentation: </li><li>Proficiency in implementing DBT tests for data validation and quality checks</li><li>Familiarity with generating and maintaining documentation using DBT's built in features</li><li>Version control: </li><li>Experience in managing DBT projects using git ,including implementing CI/CD process from the scratch</li><li>AWS Expertise: </li><li>Data STORAGE solutions: </li><li>In depth understanding of AWS S3 for data storage, including best practices for organization and security</li><li>Experience with AWS redshift for data warehousing and performance optimization</li><li>Data Integration: </li><li>Familiarity with Aws glue for ETL processes and orchestration -Nice to have</li><li>Experience with AWS lambda for serverless data processing tasks</li><li>Workflow Orchestration: </li><li>Proficiency in using Apache Airflow on AWS to design ,schedule and monitor complex data flows</li><li>Ability to integrate Airflow with AWS services and DBT models such as triggering a DBT model or EMR or reading from s3 writing to redshift</li><li>Data Lakes and Data warehousing: </li><li>Understanding the architecture of data lakes vs data warehouses and when to use each</li><li>Experience with amazon Athena for querying data directly in s3 using SQL</li><li>Monitoring and Logging: </li><li>Familiarity with AWS cloud watch for monitoring the pipelines and setting up alerts for workflow failures</li><li>Cloud Security: </li><li>Knowledge of AWS security best practices ,including IAM roles, encryption, DBT profiles access configurations</li></ul>Programming Skills:<ul><li>Python: </li><li>Proficiency in Pandas and NumPy for data analysis and manipulation</li><li>Ability to write scripts for automating ETL processes and scheduling jobs using airflow</li><li>Experience in creating custom DBT macros using jinja and Python allowing for reusable components within dbt models</li><li>Knowledge on how to implement conditional logic in DBT through python</li><li>SQL: </li><li>Advanced SQL skills, including complex joins ,window functions, CTE’s and subqueries</li></ul>Experience in optimizing SQL queries for performance and optimization

Tek Leaders Inc Interview Questions

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Tek Leaders Inc Interview Questions

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