Storing an array of data in a single column is not the greatest idea there is.
See the
First Normal Form (1NF)[
^]
And then look into the Second Normal Form (2NF) and 3NF.
Rather you should create a second table where you store the item numbers together with a key from the first table.
Table1
ID Column1 Column2
1 Hello World
2 Eat Spaghetti
Table2
ID ITEM_NO Table1_ID
1 980124 1
2 970125 1
3 781202 1
4 874562 1
5 9234567 1
6 1233456 2
7 2344556 2
8 5667789 2
9 980124 2 -- Same ITEM_NO as in row 1
When you want to get all the item numbers for a certain ID in Table1 just do like this:
SELECT ITEM_NO FROM Table1 WHERE Table1_ID = 1;
It is also easy to add or remove a single item number.