In a 30-day SQL challenge, members will be posting a video every day to cover different queries. The first query involves removing pairs of brands in the same year, based on specific criteria. By creating a unique pair ID and applying window functions, the required records can be filtered to obtain the desired output. Check the Discord channel for more details and join the challenge! Let’s help each other solve these problems and build a strong community. ๐ป๐๐ #30DaySQLQueryChallenge
Introduction
The 30-day SQL challenge has officially commenced, and for the next 30 days, a daily video will be posted covering various SQL queries. These queries have been obtained from different platforms and shared via email, LinkedIn, Discord, and various online forums. Some are beginner-level queries, while others are more intermediate or complex.
Understanding the Problem
The first query involves removing duplicate rows in a table. The input table consists of four fields: brand, year, custom 3, and custom 4. The task at hand is to identify pairs of brands that appear in the same year and keep only one instance of each pair.
| Brand | Year | Custom 3 | Custom 4 |
|---|---|---|---|
| Apple | 2020 | … | … |
| Samsung | 2020 | … | … |
| … | … | … | … |
Key Takeaways
- Identifying pairs of brands in the same year.
- Removing duplicate rows based on specific conditions.
- Finding solutions through community collaboration – join the Discord and share your solutions!
Solving the Problem
To solve this problem, the original data set is to be downloaded and provided in the Discord channel. Using PostgreSQL or any preferred database, the task involves identifying pairs of brands in the same year and eliminating duplicate records based on specified conditions.
Plan of Action
- Creating a unique pair ID for each pair of records.
- Applying a row number window function to eliminate one record from each pair.
- Filtering records based on specific conditions to obtain the final output.
The solution to the problem involves SQL query execution to ultimately remove duplicate rows based on the given conditions. For detailed information and discussion, join the Discord and contribute to the 30-day SQL challenge!
I hope you enjoy the challenge and engage in open discussions on problem-solving methodologies.
Remember, the key to improving your SQL skills is through practice and collaboration.
Happy querying! ๐ฉโ๐ป
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