my need is to be able to make a list of private messages and take the last private message record. For example, the structure of the data table:
id pid from_userid to_userid content time
10 a b hi 01
21 b a hello 02
3 1 a b hihi 04
40 a c test 09
54 c a test1 11
the list that needs to be obtained is
a b hihi 04
c a test1 11
how to write this sql sentence?
do you want to: the last record of others trusting my and my private trust respectively?
this sql statement, under thinkphp5.17 tp there is another problem. My sql statement is executed incorrectly. I can t see the error statement in the tract panel or runtime log. I want to see what I did wrong and what I think. ...
id name relation 1 n1 r1 2 n2 r2 3 n4 r1 4 n5 r1 5 n6 r2 6 n6 r1 the relation relationship of the table is shown above where the relation field indicates the relationship between the cur...