tweet_id is the primary key for this table, which contains all the tweets in a social media app.
The task is to write an SQL query to find the IDs of the invalid tweets. A tweet is invalid if the number of characters used in the content of the tweet is strictly greater than 15.
Here's an example to better illustrate the problem:
|1||Vote for Biden|
|2||Let us make America great again!|
Tweet 1 has a length of 14. It's a valid tweet.
Tweet 2 has a length of 32. It's an invalid tweet.
In this post, we'll delve into two MSSQL solutions. Both effectively solve the problem but using different functions — highlighting their unique strengths, weaknesses, and performance metrics.
The first solution uses the
LEN function to calculate the length of the tweet content:
SELECT tweet_id FROM Tweets WHERE LEN(content) > 15
The second solution differs from the first by using the
DATALENGTH function instead of
SELECT tweet_id FROM Tweets WHERE DATALENGTH(content) > 15
These two solutions effectively determine the invalid tweets based on the content length, with the second solution performing significantly better on LeetCode. However, performance may vary in real-world RDMS due to different factors, such as data volume, system hardware, SQL server configurations, etc.
Here's a ranking of these solutions based on LeetCode performance:
- Source Code 2
- Source Code 1
You can find the original problem at LeetCode.
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