Occurence of character in a string

Question

How can i find how many occurrence of a character in a string?
Let's say: 010101010101010: there is 8 0 in that string.

Answer 1

Here's just a different take on the same old problem, tested on 10g ... ;-)
WITH t AS (SELECT '010101010101010' col1
             FROM dual
SELECT SYS_CONNECT_BY_PATH(symbol || ':' || TO_CHAR(no_of_sym), ' ') sym_stat
  FROM (SELECT SUBSTR(t.col1, LEVEL, 1) symbol
             , COUNT(*)                 no_of_sym
             , ROW_NUMBER() OVER (ORDER BY SUBSTR(t.col1, LEVEL, 1)) rn
          FROM t
       CONNECT BY LEVEL <= LENGTH(t.col1)
         GROUP BY SUBSTR(t.col1, LEVEL, 1)
WHERE connect_by_isleaf = 1
START WITH rn = 1
CONNECT BY PRIOR rn = rn - 1
=> "0:8 1:7"C.