MySQL 8.0 - implementing GROUP_CONCAT Size Limit in Large Data Sets
I'm updating my dependencies and I'm working with a question while trying to use the `GROUP_CONCAT` function in MySQL 8.0 with a table that has a important amount of data. My query is intended to concatenate values from multiple rows into a single string, but it seems to truncate the output when the result exceeds the maximum allowed length. I've checked the `group_concat_max_len` variable and it is set to 1024 bytes, which I believe is too small for the data I'm working with. Here's the SQL query I'm using: ```sql SELECT user_id, GROUP_CONCAT(comment SEPARATOR ', ') AS comments FROM comments GROUP BY user_id; ``` When I run this, I get truncated results for some users. I tried setting the `group_concat_max_len` variable to a larger value using the following statement: ```sql SET SESSION group_concat_max_len = 10000; ``` However, even after doing this, I still see the concatenated string being cut off. Additionally, I am unsure if this change will continue across sessions or if I need to set it every time I run my application. I have tried to investigate the scenario further and found that the maximum allowed length for `GROUP_CONCAT` is 1024 bytes by default. Am I missing something in my approach? Should I manage this variable at the system level for it to have a lasting effect instead of setting it at the session level? Any insights on how to effectively handle this would be greatly appreciated! Any suggestions would be helpful.