Simple and practical PHP unlimited classification source code sharing (good idea)

The following code creates an SQL statement for a database:
Copy codeThe Code is as follows:
//////////////
///// Database design and example of unlimited Classification
//////////////
Mysql> create database db_kind;
Query OK, 1 row affected

Mysql> use db_kind;
Database changed
Mysql> create table tb_kind (
-> Id int not null auto_increment primary key,
-> Pid int,
-> Path varchar (200)
-> );
Query OK, 0 rows affected

Mysql> insert into tb_kind values (null, "news", 0, 0 );
Query OK, 1 row affected

Mysql> insert into tb_kind values (null, "video", 0, 0 );
Query OK, 1 row affected

Mysql> insert into tb_kind values (null, "image", 0, 0 );
Query OK, 1 row affected

Mysql> insert into tb_kind values (null, "blog", 0, 0 );
Query OK, 1 row affected

Mysql> insert into tb_kind values (null, "Sports News", 1, "0-1 ");
Query OK, 1 row affected

Mysql> insert into tb_kind values (null, "Entertainment News", 1, "0-1 ");
Query OK, 1 row affected

Mysql> insert into tb_kind values (null, "Financial News", 1, "0-1 ");
Query OK, 1 row affected

Mysql> select * from db_kind;
ERROR 1146: Table 'db _ kind. db_kind 'doesnot exist
Mysql> select * from tb
_ Kind;
+ ---- + ---------- + ----- + ------ +
| Id | pname | pid | path |
+ ---- + ---------- + ----- + ------ +
| 1 | news | 0 | 0 |
| 2 | video | 0 | 0 |
| 3 | image | 0 | 0 |
| 4 | blog | 0 | 0 |
| 5 | sports news | 1 | 0-1 |
| 6 | entertainment news | 1 | 0-1 |
| 7 | Financial News | 1 | 0-1 |
+ ---- + ---------- + ----- + ------ +
7 rows in set
Mysql> insert into tb_kind values (null, "basketball news", 5, "0-1-5 ");
Query OK, 1 row affected

Mysql> insert into tb_kind values (null, "Football news", 5, "0-1-5 ");
Query OK, 1 row affected

Mysql> select * from tb_kind;
+ ---- + ---------- + ----- + ------- +
| Id | pname | pid | path |
+ ---- + ---------- + ----- + ------- +
| 1 | news | 0 | 0 |
| 2 | video | 0 | 0 |
| 3 | image | 0 | 0 |
| 4 | blog | 0 | 0 |
| 5 | sports news | 1 | 0-1 |
| 6 | entertainment news | 1 | 0-1 |
| 7 | Financial News | 1 | 0-1 |
| 8 | basketball news | 5 | 0-1-5 |
| 9 | football news | 5 | 0-1-5 |
+ ---- + ---------- + ----- + ------- +
9 rows in set

Mysql> insert into tb_kind values (null, "NBA", 8, "0-1-5-8 ");
Query OK, 1 row affected

Mysql> insert into tb_kind values (null, "CBA", 8, "0-1-5-8 ");
Query OK, 1 row affected

Mysql> select * from tb_kind;
+ ---- + ---------- + ----- + --------- +
| Id | pname | pid | path |
+ ---- + ---------- + ----- + --------- +
| 1 | news | 0 | 0 |
| 2 | video | 0 | 0 |
| 3 | image | 0 | 0 |
| 4 | blog | 0 | 0 |
| 5 | sports news | 1 | 0-1 |
| 6 | entertainment news | 1 | 0-1 |
| 7 | Financial News | 1 | 0-1 |
| 8 | basketball news | 5 | 0-1-5 |
| 9 | football news | 5 | 0-1-5 |
| 10 | NBA | 8 | 0-1-5-8 |
| 11 | CBA | 8 | 0-1-5-8 |
+ ---- + ---------- + ----- + --------- +
11 rows in set

Mysql> select concat (path, "-", id) from tb_kind;
+ --------------------- +
| Concat (path, "-", id) |
+ --------------------- +
| 0-1 |
| 0-2 |
| 0-3 |
| 0-4 |
| 0-1-5 |
| 0-1-6 |
| 0-1-7 |
| 0-1-5-8 |
| 0-1-5-9 |
| 0-1-5-8-10 |
| 0-1-5-8-11 |
+ --------------------- +
11 rows in set

Mysql> select concat (path, "-", id) from tb_kind;
+ --------------------- +
| Concat (path, "-", id) |
+ --------------------- +
| 0-1 |
| 0-2 |
| 0-3 |
| 0-4 |
| 0-1-5 |
| 0-1-6 |
| 0-1-7 |
| 0-1-5-8 |
| 0-1-5-9 |
| 0-1-5-8-10 |
| 0-1-5-8-11 |
+ --------------------- +
11 rows in set

Mysql> select concat (path, "-", id) as abs from tb_kind order by abs. path;
ERROR 1054: Unknown column 'abs. path' in 'order clause'
Mysql> select concat (path, "-", id) as abs from tb_kind order by abs

+ ------------ +
| Abs |
+ ------------ +
| 0-1 |
| 0-1-5 |
| 0-1-5-8 |
| 0-1-5-8-10 |
| 0-1-5-8-11 |
| 0-1-5-9 |
| 0-1-6 |
| 0-1-7 |
| 0-2 |
| 0-3 |
| 0-4 |
+ ------------ +
11 rows in set
Mysql> select concat (path, "-", id) as, id, name, path abs from tb_kind order by abs;
ERROR 1064: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'id, name, path abs from tb_kind order by abs 'at line 1
Mysql> select concat (path, "-", id) as abs,
Id, pname, path abs from tb_kind order by abs;
+ ------------ + ---- + ---------- + --------- +
| Abs | id | pname | abs |
+ ------------ + ---- + ---------- + --------- +
| 0-1 | 1 | news | 0 |
| 0-1-5 | 5 | sports news | 0-1 |
| 0-1-5-8 | 8 | basketball news | 0-1-5 |
| 0-1-5-8-10 | 10 | NBA | 0-1-5-8 |
| 0-1-5-8-11 | 11 | CBA | 0-1-5-8 |
| 0-1-5-9 | 9 | football news | 0-1-5 |
| 0-1-6 | 6 | entertainment news | 0-1 |
| 0-1-7 | 7 | Financial News | 0-1 |
| 0-2 | 2 | video | 0 |
| 0-3 | 3 | image | 0 |
| 0-4 | 4 | blog | 0 |
+ ------------ + ---- + ---------- + --------- +
11 rows in set
Mysql>

The following is the php source file:
Copy codeThe Code is as follows:
<! DOCTYPE html PUBLIC "-// W3C // dtd xhtml 1.0 Transitional // EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<Html xmlns = "http://www.w3.org/1999/xhtml">
<Head>
<Meta http-equiv = "Content-Type" content = "text/html; charset = UTF-8"/>
<Title> untitled document </title>
</Head>
<Body>
<! -- Display Results
News
Sports News
Basketball news
NBA
CBA
Football news
Entertainment News
Financial News
Video
Image
Blog
-->
<?
$ Conn = mysql_connect ("localhost", "root", "root ");
Mysql_select_db ("db_kind ");
Mysql_query ("set names utf8 ");
$ SQL = "select concat (path, '-', id) as abspath, id, pname, path from tb_kind order by abspath ";
$ Rs = mysql_query ($ SQL );
While ($ result = mysql_fetch_assoc ($ rs )){
$ Num = count (explode ("-", $ result [path])-1;
$ New_str = str_repeat ("---", $ num );
Echo $ new_str. $ result [pname];
Echo "<br> ";
}
$ Str = str_repeat ("=", 10 );
Echo $ str;
$ Num = count (explode ("-", "0-1-5-8")-1;
Echo $ num;
?>
</Body>
</Html>

In the above Code, there is actually a space in the middle of the input effect is very good, please test locally. The layout is messy due to editor problems.