mysql百萬數(shù)據(jù)sum很慢 mysql怎么實現(xiàn)遞歸查詢數(shù)據(jù)?
mysql怎么實現(xiàn)遞歸查詢數(shù)據(jù)?mysql> create table treeNodes->(-> id int primary key,-> nodename varchar(20
mysql怎么實現(xiàn)遞歸查詢數(shù)據(jù)?
mysql> create table treeNodes->(-> id int primary key,-> nodename varchar(20),-> pid int->)Query OK,0行受影響(0.09秒)mysql> select*from treeNodes-------------------------| id | nodename | pid |---------|
1 | A | 0 | |
2 | B | 1 | | C | 1 | 4 | D | 2 | 5 | E |2 | | | | | | | | | | 15 | O | 12 | |
16 | P | 15 | | |
17 | Q | 15 |---------------17行(0.00秒)