Concatenation operator

This will be used to combine two strings only.
Syntax: concat (string1, string2)

Ex:

select concat('computer',' operator') from dual;

output

concat('computer',' operator')
--------------------------------
computer operator

some more example

select concat('science',' park') from dual;
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science park

Note

If you want to combine more than two strings you have to use concatenation operator( || )

select 'How'||'are'||'you' from dual;
----------------------------------------------
Howareyou