String Contains Another String
In postgres, you can check if a string contains another string using the position
function.
> select position('One' in 'One Two Three');
position
----------
1
It returns the 1-based index of the first character of the first match of that substring.
> select position('Four' in 'One Two Three');
position
----------
0
If the substring doesn't appear within the string, then the result is 0.
Thus, you can determine if a string contains another string by checking if
the value resulting from position is greater than 0.