Question

is there a way to write an sql query that finds all rows where the field value is a substring of a given string.

Example:

table names

Name      |      Nickname
rohit            iamrohitbanga
banga            rohitnick
sinan            unur

query should be something like

select * from names where Name is a substring of "who is rohit";   // to get first row
select * from names where Nickname is a substring of "who is rohitnick";   // to get second row
select * from names where Name is a substring of "who is unur and banga"
or Nickname is substring of "who is unur and banga";   // to get second and third row

How is it possible?

If it is not possible then i’ll have to achieve that behaviour in java. i am using jdbc:mysql driver to connect to the database.

Update
your solutions work

now a bit of a twist.
if we want to check if a substring of the field occurs as a substring of the string that we specify.

select * from names where Name is a substring of "who is sina";   // to get third row

Answer 1

If one of Name or Nickname has to be found within the text use

SELECT *
FROM names
WHERE instr("who is Rohit", Name) > 0
   OR instr("who is Rohit", Nickname) > 0

No index can be used for that, so it might take long for large tables.