NTR - remove group_contact to prevent string cutting for private notes

[teiling88]

We have a strange issue in the c:geo application. The group_concat is cutting private notes cause of mysql default string limitations in group_contact. We don't need this cause we have no duplicate entries in coordinates.

For more details please see https://github.com/cgeo/cgeo/issues/13651

[bekuno]

OK, I don't understand why group_concat can cause the issue but this is ocde specific so let's merge it

see

• https://dev.mysql.com/doc/refman/5.7/en/server-system-variables.html#sysvar_group_concat_max_len
• https://sebhastian.com/mysql-group_concat-limit/

[kojoty]

OK, I don't understand why group_concat can cause the issue but this is ocde specific so let's merge it

see

• https://dev.mysql.com/doc/refman/5.7/en/server-system-variables.html#sysvar_group_concat_max_len
• https://sebhastian.com/mysql-group_concat-limit/

Not sure if it is worth the discussion - I assume you know what you need anyway :)

I understand that group_concat has limit so if there are duplicated records descriptions of all such records will be concatenated but result could be no longer than mysql-group_concat-limit - this is clear

I didn't understand why it cut the notes - I assumed this is not in the same column so why description has anything to notes?

but please note I didn't study the whole story :)

[murggel]

group_concat is used for OCPL as well. Can the problem occur there as well?

https://github.com/opencaching/okapi/blob/233361623d6a4bcc7790f40a8164b14df1f7fc66/okapi/services/caches/geocaches/WebService.php#L1107

I didn't understand why it cut the notes - I assumed this is not in the same column so why description has anything to notes?

For me it seems that the content of the note is saved in the description field...

[teiling88]

The description field with type 2 is the private note in the ocde branch. This issue could happen in ocpl as well.

[rapotek]

group_concat is used for OCPL as well. Can the problem occur there as well?

https://github.com/opencaching/okapi/blob/233361623d6a4bcc7790f40a8164b14df1f7fc66/okapi/services/caches/geocaches/WebService.php#L1107

I didn't understand why it cut the notes - I assumed this is not in the same column so why description has anything to notes?

For me it seems that the content of the note is saved in the description field...

group_concat can be safely removed here, too; cache_notes table has a primary key of (cache_id, user_id), so for single user there cannot be more than one record with the same cache_id. The grouping here is on cache_id so the result would be the same as for direct select of desc without group_concat.