php - LAST_INSERT_ID() how it works at multi-users environment -

check question first:
inserting automatically generated index table table
got function "last_insert_id()" required
question is: i'm using in php script, if user inserted data in "table1" , before insert "id" "table2" user inserted data "table1"...then "id" function retrieve first user, id or id of second user "the last one"??
wish retrieve "id" user himself "the first user" inserted, if doesn't achieve how it??

last_insert_id() gives last autogenerated id on connection execute on, not return last insert id globally produced mysql server.