SQL String: Counting Words inside a String - sql-server

Question

I searched through many of the questions here but all I found with decent answer is for different language like Javascript etc.
I have a simple task in SQL that I can't seem to find a simple way to do.
I just need to count the number of "words" inside a SQL string (a sentence). You can see why "words" is in quotes in my examples. The "words" are delimited by white space.
Sample sentences:
1. I am not your father.
2. Where are your brother,sister,mother?
3. Where are your brother, sister and mother?
4. Who are you?
Desired answer:
1. 5
2. 4
3. 7
4. 3
As you can see, I need to count the "words" disregarding the symbols (I have to treat them as part of the word). So in sample no. 2:
(1)Where (2)are (3)your (4)brother,sister,mother? = 4
I can handle the multiple whitespaces by doing a replace like this:
REPLACE(string, ' ', ' ') -> 2 whitespaces to 1
REPLACE(string, ' ', ' ') -> 3 whitespaces to 1 and so on..
What SQL function can I use to do this? I use SQL Server 2012 but needs a function that works in SQL Server 2008 as well.

Answer 1

Here is one way to do it:
Create and populate sample table (Please save is this step in your future questions)
DECLARE #T AS TABLE
(
id int identity(1,1),
string varchar(100)
)
INSERT INTO #T VALUES
('I am not your father.'),
('Where are your brother,sister,mother?'),
('Where are your brother, sister and mother?'),
('Who are you?')
Use a cte to replace multiple spaces to a single space (Thanks to Gordon Linoff's answer here)
;WITH CTE AS
(
SELECT Id,
REPLACE(REPLACE(REPLACE(string, ' ', '><' -- Note that there are 2 spaces here
), '<>', ''
), '><', ' '
) as string
FROM #T
)
Query the CTE - length of the string - length of the string without spaces + 1:
SELECT id, LEN(string) - LEN(REPLACE(string, ' ', '')) + 1 as CountWords
FROM CTE
Results:
id CountWords
1 5
2 4
3 7
4 3

Answer 2

This is a minor improvement of #ZoharPeled's answer. This can also handle 0 length values:
DECLARE #t AS TABLE(id int identity(1,1), string varchar(100))
INSERT INTO #t VALUES
('I am not your father.'),
('Where are your brother,sister,mother?'),
('Where are your brother, sister and mother?'),
('Who are you?'),
('')
;WITH CTE AS
(
SELECT
Id,
REPLACE(REPLACE(string,' ', '><'), '<>', '') string
FROM #t
)
SELECT
id,
LEN(' '+string)-LEN(REPLACE(string, '><', ' ')) CountWords
FROM CTE

Answer 3

To handle multiple spaces too, use the method shown here
Declare #s varchar(100)
set #s='Who are you?'
set #s=ltrim(rtrim(#s))
while charindex(' ',#s)>0
Begin
set #s=replace(#s,' ',' ')
end
select len(#s)-len(replace(#s,' ',''))+1 as word_count
https://exploresql.com/2018/07/31/how-to-count-number-of-words-in-a-sentence/

Answer 4

I found this query more useful than the first. it omit extra characters and numbers and symbols, so it would count just words within a passage...
drop table if exists #t
create table #t (id int identity(1,1), c1 varchar(2000))
insert into #t (c1)
values
('Alireza Sattarzadeh Farkoush '),
('yes it is the   best .'),
('abc def ghja a the . asw'),
('?>< 123 ...!  z a b'),
('Wallex is   the greatest exchange in the .. world a after binance ...!')
select c1 , Count(*)
from (
select id, c1, value  
from #t t
cross apply (
select rtrim(ltrim(value)) as value from string_split(c1,' ')) a
where len(value) > 1 and value like '%[a-Z]%'
) Final
group by c1