sql - Updating a column in MySQL using its previous value -


this question has answer here:

i have table in mysql 'url_map' 2 columns: id, url values populated in it. this:

+----+-----------------------------------------+ | id | url | +----+-----------------------------------------+ | 1 | http://myserver.mywebsite.com/file1.txt | | 2 | http://myserver.mywebsite.com/file2.txt | +----+-----------------------------------------+

my requirement update 'url' of every row in table new value using it's previous value.

+----+---------------------------------------------+ | id | url | +----+---------------------------------------------+ | 1 | https://mynewserver.mywebsite.com/file1.txt | | 2 | https://mynewserver.mywebsite.com/file2.txt | +----+---------------------------------------------+

if see changes, in every row, value of 'url' has been changed

  • http:// https://
  • myserver mynewserver

rest other things in url kept previously.

can please me out in writing query ?

you can use previous value directly in update statement

update your_table t set t.url = replace(replace(t.url, 'http://', 'https://'), 'myserver', 'mynewserver')

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