Oracle SQL count occurances of character in VARCHAR
What version of Oracle?

If you're using Oracle 11.1 or later, you can use REGEXP_COUNT

  1* select regexp_count( '11001110', '1' ) from dual
SQL&gt; /

REGEXP_COUNT('11001110','1')
----------------------------
                           5


In earlier versions, there are various less elegant options such as

SQL&gt; select length( '11001110' ) - length( replace( '11001110', '1' ) ) cnt
  2    from dual;

       CNT
----------
         5