MySQL Subquery (or join?) to Select value of another tables ID -


i have taken @ following answer: select rows table row in table same id has particular value in column

which did ok job in confusing me far sub-queries.

my table looks this:

field   type ------  ------------ id      int(11) parent  int(11) title   varchar(255) uri     varchar(255) perms   varchar(255)

what trying do, select records , show parent , parent_name (if parent exists.

so example output, if had 2 rows

foo id of 1 & bar id of 2 , child of 1

foo null bar foo 1

my sql looks this:

select id,parent,title,uri,perms  ls_menu_manager parent in ( select title parent_name ls_menu_manager parent=id )

but not work intended. think have gone , confused myself appreciated.

it looks me should try using left join

select ch.id, ch.parent, ch.title, ch.uri, ch.perms, pr.title parent_name   ls_menu_manager ch   left join ls_menu_manager pr     on pr.id = ch.parent

this display rows in ls_menu_manager, , parent name when 1 present.
if no parent defined particular row, parent_name show null.
if want rows have parent, change left join natural join, removing left keyword.

select ch.id, ch.parent, ch.title, ch.uri, ch.perms, pr.title parent_name   ls_menu_manager ch   join ls_menu_manager pr     on pr.id = ch.parent

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