I have a MySQL database. There is one table has thousands rows of data. I need to add one string to every rows of one column.
It is a very popular scenario. Looks like in the middle of using one database, the developer need a new column with a default value in it.
Yes, he can setup a default value, but what about the existing data. The answer is shown below.
sample_table
+------+------+--------------+ | fieldA | fieldB | fieldC | | 22 | star | 2 | | 23 | super | 2 | | 24 | savemore | 1 | | 25 | justtolook | 4 | | 26 | bestbook | 4 |
I add this string to all rows of fieldB, just after the existing data.
The SQL script is used to do this job shown as below
update sample_table set fieldB = concat(fieldB ,'.html');
Then after this script.
+------+------+--------------+ | fieldA | fieldB | fieldC | | 22 | star.html | 2 | | 23 | super.html | 2 | | 24 | savemore.html | 1 | | 25 | justtolook.html | 4 | | 26 | bestbook.html | 4 |