PHP MySQL consolidate column where other column has duplicates - php

Question

I have a MySQL table that has three columns, the first is a unique key (INT(11) AUTO_INCREMENT), the next is an indexed value (VARCHAR(255)) and the third is a description (TEXT). There are duplicate values in the second column, but each row has a different description. I want to remove all rows where the second column is duplicated but append each description of the same indexed value to the first instance the value, and breaking string with a semicolon and space.
For example, my table looks like this:
cid | word | description
------------------------------
1 | cat | an animal with wiskers
2 | cat | a house pet
3 | dog | a member of the canine family
4 | cat | a cool person
I want to change the table to look like this:
cid | word | description
------------------------------
1 | cat | an animal with wiskers; a house pet; a cool person
3 | dog | a member of the canine family
I'm not adverse to using a PHP script to do this, but would prefer MySQL. The table has over 170,000 rows and would take PHP a long time to loop over it.

Answer 1

SQL:
select `cid`,`word`,group_concat(`description` SEPARATOR '; ') as `description` from `test_table` group by `word`;
Ok.. you can copy all the data into another table, and rename it then..
insert into `test_new` (`cid`,`word`,`desc`) (select `cid`,`word`,group_concat(`desc` SEPARATOR '; ') as `description` from `test_table` group by `word`);
mysql> describe `test_new`;
+-------+----------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| id | int(11) | YES | | NULL | |
| word | char(10) | YES | | NULL | |
| desc | text | YES | | NULL | |
+-------+----------+------+-----+---------+-------+
3 rows in set (0.00 sec)
mysql> select * from `test_new`;
+------+------+---------------------+
| id | word | desc |
+------+------+---------------------+
| 1 | cat | desc1; desc2; desc4 |
| 3 | dog | desc3 |
+------+------+---------------------+
2 rows in set (0.00 sec)

Answer 2

As was mentioned before, you can create a new table and copy the info, you can also do it in two steps, but only if there´s no problem with modifying the old table:
UPDATE tableOld AS N1, tableOld AS N2
SET N1.description = concat(concat(N1.description,"; "),N2.decription))
WHERE N2.word = N1.word
insert into tableNew (cid,name,description)select * from tableOld group by word