Manual talk:User properties table

Possible values
Where are the possible values for up_property? Emijrp 13:33, 9 January 2012 (UTC)
 * Those listed in Manual:$wgDefaultUserOptions. Examples: ,  ,  . That is now part of the page. --88.130.114.181 15:43, 15 January 2014 (UTC)

Does it make sense to delete default or invalid preferences?
Just one example from Wikipedia: [enwiki]> select up_value, count(up_value) from user_properties where up_property = 'skin' group by up_value; +-+-+ +-+-+ +-+-+ 15 rows in set (42.87 sec)
 * up_value   | count(up_value) |
 * |        7180008 |
 * 0          |           53977 |
 * 1          |            1754 |
 * 2          |            3056 |
 * amethyst   |            1290 |
 * chick      |           31861 |
 * cologneblue |          86625 |
 * minerva    |             105 |
 * modern     |           80541 |
 * monobook   |         2190517 |
 * myskin     |           16178 |
 * nostalgia  |           21144 |
 * simple     |           14116 |
 * standard   |           34181 |
 * vector     |          162403 |

I can understand "monobook", "modern", and "cologneblue", but:
 * Is it in any way useful to have 162403 rows with the "vector" value, which is default?
 * Is it in any way useful to have rows for "chick", "amethyst", and "nostalgia", which are unlikely to ever come back?
 * What are the empty string values doing?
 * What are the number values?

Another example is the Math properties, which I reported at T166369.

Is there any reason not to clean such things up somehow? Or is it just hassle with no benefit? --Amir E. Aharoni (talk) 20:56, 28 May 2017 (UTC)