You can use something similar to this. This gets the length of the string, then substracts the length of the string with the spaces removed. By then adding the number one to that should give you the number of words:
Select length(yourCol) - length(replace(yourcol, ' ', '')) + 1 NumbofWords
from yourtable
See SQL Fiddle with Demo
If you use the following data:
CREATE TABLE yourtable
(yourCol varchar2(15))
;
INSERT ALL
INTO yourtable (yourCol)
VALUES ('Hello To Oracle')
INTO yourtable (yourCol)
VALUES ('oneword')
INTO yourtable (yourCol)
VALUES ('two words')
SELECT * FROM dual
;
And the query:
Select yourcol,
length(yourCol) - length(replace(yourcol, ' ', '')) + 1 NumbofWords
from yourtable
The result is:
| YOURCOL | NUMBOFWORDS |
---------------------------------
| Hello To Oracle | 3 |
| oneword | 1 |
| two words | 2 |
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