Question

I have the XML field in one table. I want to update that field. Here is the XML format:

<data><user>abcd</user></data>

I want to change the value abcd to efgh. How can I achieve this?

Answer 1

Here are some examples to show how to update to constants, variables or using existing column info:

declare @x table(i bigint not null identity(1,1), x xml, y nvarchar(64))
declare @z nvarchar(64) = 'sql variable data'

insert @x select '<data><user>abcd</user></data>', 'sql column data 1'
insert @x select '<data><user>abcd</user></data>', 'sql column data 2'
insert @x select '<data><user>abcd</user></data>', 'sql column data 3'

update @x
set x.modify('replace value of (/data/user/text())[1] with ''efgh''')
where i=1

update @x
set x.modify('replace value of (/data/user/text())[1] with sql:column(''y'')')
where i=2

update @x
set x.modify('replace value of (/data/user/text())[1] with sql:variable(''@z'')')
where i=3

select * from @x

Output:

i   x                                           y
1   <data><user>efgh</user></data>              sql column data 1
2   <data><user>sql column data 2</user></data> sql column data 2
3   <data><user>sql variable data</user></data> sql column data 3