MySQL How to print the latest purchase product information in the group

How MySQL prints the latest purchased product information in the array
There is a book table (Stitle is the product name, an ID can purchase more than one book, such as the user ID 1 purchase a, B 2 products)

SQL Code

  
   Field  ID      stitle    time      1       A, B,     2011-01-01      2       c,d,     2011-01-02      3       A,       2011-01-03       4       b,e,     2011-01-04      5       C,       2011-01-05

Now ask how to print the latest first 5 purchased product names, the order of display should be:


C,b,e,a,d







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SQL Code

Select Left (Group_concat (Stitle), ten) from (select TRIM (', ' from Stitle) as Stitle from ' book ' ORDER by Time DESC LIMIT 5) A
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I think it would be nice to search in reverse order 5.

And then into the array, because the repetition of less than 5 items repeats the process
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In fact, he must have a product catalog why not use it?
  
  

   
   SQL Code
   
   
DROP TABLE IF EXISTS ' T1 '; CREATE TABLE t1 (ID int primary key auto_increment,stitle varchar (), time date), insert into T1 values (null, ' A-B ', ' 2011-01  -01 '); insert into T1 values (null, ' c,d ', ' 2011-01-02 '); insert into T1 values (null, ' A ', ' 2011-01-03 '); INSERT into T1 values  (NULL, ' b,e ', ' 2011-01-04 '); insert into T1 values (null, ' C ', ' 2011-01-05 ');D rop TABLE IF EXISTS ' T2 ';  CREATE TABLE t2 (ID int primary KEY auto_increment,name varchar), insert into T2 values (null, ' a '); INSERT into T2 values  (NULL, ' B '); INSERT into T2 values (null, ' C '); INSERT into T2 values (null, ' d '); INSERT into T2 values (null, ' E '); INSERT into T2 values (null, ' F '); Select T1.id, T2.name as Stitle, t1.time from T1, T2 where Find_in_set (T2.name, t1.stitle) Order by T1.time desc LIMIT 5
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     SQL Code
     
     
DROP TABLE IF EXISTS ' t '; CREATE TABLE t (ID int PRIMARY key auto_increment,stitle varchar (), time date); INSERT into t values (' ', ' A, B, ', str_to_date (' 2011-01-01 ', '%y-%m-%d ')); INSERT into t values (' ', ' c,d, ', ' str_to_date (' 2011-01-02 ', '%y-%m-%d ')); INSERT into t values (', ' A, ', Str_to_date (' 2011-01-03 ', '%y-%m-%d ')); INSERT into t values (' ', ' b,e, ', ' str_to_date (' 2011-01-04 ', '%y-%m-%d ')) and insert into t values (' ', ' C, ', Str_to_date (' 2011-01-05 ', '%y-%m-%d ')); select * FROM (select Id,substring (stitle,1,1) as newsitle,time,1 as Order1 from Tunion allselect id,substring (stitle,3,1) as newsitle,time,2 as Order1 from T) awhere a.newsitle! = "Orde R by Time desc,order1 ASC Limit 0,5;+----+----------+------------+--------+| ID | Newsitle | Time |  Order1 |+----+----------+------------+--------+| 5 | C |      2011-01-05 |  1 | | 4 | B |      2011-01-04 |  1 | | 4 | e |      2011-01-04 |  2 | | 3 | A |      2011-01-03 |  1 | | 2 | C |      2011-01-02 | 1 |+----+----------+------------+--------+  
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