SQL query with most recent name and total count - mysql

Question

I already have a table, "table_one", set up on phpMyAdmin that has the following columns:
USER_ID: A discord user ID (message.author.id)
USER_NAME: A discord username (message.author.name)
USER_NICKNAME: The user's display name on the server (message.author.display_name)
TIMESTAMP: A datetime timestamp when the message was entered (message.created_at)
MESSAGE CONTENT: A cleaned input keyword to successful completion of content, just for this example consider "apple" or "orange" as the two target keywords.
What I'd like as a result is a view or query that returns a table with the following:
The user's most recent display name (USER_NICKNAME), based off the most recent timestamp
The total number of times a user has entered a specific keyword. Such as confining the search to only include "apple" but not instances "orange"
My intention is that if a user entered a keyword 10 times, then changed their server nickname and entered the same keyword 10 more times, the result would show their most recent nickname and that they entered the keyword 20 times in total.
This is the closest I have gotten to my desired result so far. The query correctly groups instances where user has changed their nickname based on the static discord ID, but I would like it to retain this functionality while instead showing the most recent USER_NICKNAME instead of a USER_ID:
SELECT USER_ID, COUNT(USER_ID)
FROM table_one
WHERE MESSAGE_CONTENT = 'apple'
GROUP BY USER_ID

Answer 1

I don't think there is an uncomplicated way to do this. In Postgres, I would use the SELECT DISTINCT ON to get the nickname, but in MySQL I believe you are limited to JOINing grouped queries.
I would combine two queries (or three, depending how you look at it).
First, to get the keyword count, use your original query:
SELECT USER_ID, COUNT(USER_ID) as apple_count
FROM table_one
WHERE MESSAGE_CONTENT = 'apple'
GROUP BY USER_ID;
Second, to get the last nickname, group by USER_ID without subsetting rows and use the result as a subquery in a JOIN statement:
SELECT a.USER_ID, a.USER_NICKNAME AS last_nickname
FROM table_one a
INNER JOIN
(SELECT USER_ID, MAX(TIMESTAMP) AS max_ts
FROM table_one
GROUP BY USER_ID) b
ON a.USER_ID = b.USER_ID AND TIMESTAMP = max_ts
I would then JOIN these two, using a WITH statement to increase the clarity of what's going on:
WITH
nicknames AS
(SELECT a.USER_ID, a.USER_NICKNAME AS last_nickname
FROM table_one a
INNER JOIN
(SELECT USER_ID, MAX(TIMESTAMP) AS max_ts
FROM table_one
GROUP BY USER_ID) b
ON a.USER_ID = b.USER_ID AND TIMESTAMP = max_ts),
counts AS
(SELECT USER_ID, COUNT(USER_ID) AS apple_count
FROM table_one
WHERE MESSAGE_CONTENT = 'apple'
GROUP BY USER_ID)
SELECT nicknames.USER_ID, nicknames.last_nickname, counts.apple_count
FROM nicknames
INNER JOIN counts
ON nicknames.USER_ID = counts.USER_ID;