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create table treestructure(name varchar(50), path varchar(100), pos_left int,pos_right int,pos_level int)
insert into treestructure(name, pos_left,pos_right ,pos_level ) values('folder1', 207, 214, 1);
insert into treestructure(name, pos_left,pos_right ,pos_level ) values('file1', 208, 209, 2);
insert into treestructure(name, pos_left,pos_right ,pos_level ) values('file2', 210, 211, 2);
insert into treestructure(name, pos_left,pos_right ,pos_level ) values('file3', 212, 213, 2);
update treestructure t
left join treestructure ts on ts.pos_level=t.pos_level-1 and t.pos_left between ts.pos_left and ts.pos_right and t.pos_right between ts.pos_left and ts.pos_right
set t.path=(case when t.pos_level=1 then t.name else concat(ts.name,'/',t.name) end);
select*from treestructure
| name | path | pos_left | pos_right | pos_level |
|---|---|---|---|---|
| folder1 | folder1 | 207 | 214 | 1 |
| file1 | folder1/file1 | 208 | 209 | 2 |
| file2 | folder1/file2 | 210 | 211 | 2 |
| file3 | folder1/file3 | 212 | 213 | 2 |