SQL statement to retrieve specific string - sql

Question

I'm trying to extract a number from a Notes column. I only want the number if it is preceded by a specific string of characters. The number can be 5 or 6 characters long, and may eventually go up to 7 or more in the future.
What combination of LEFT, RIGHT, CHARINDEX, or SUBSTRING do I need to utilize to accomplish this? or do I need to use something else altogether? I haven't been able to figure anything out that works.
The Notes column contains lots of different kinds of notes as well, so that's been making it difficult.
Thanks in advance.
EDIT: Sorry, here's some sample data and expected output.
EDIT2: Sorry again, I should've made the sample data a bit more clear. There are multiple numbers, but I only want the numbers that are preceded by 'Account #'.
Sample Data Output
'Account #12345' 12345
'Account #123456' 123456
'Random #12345' NULL
'Account #1234567' 1234567
'12345' NULL
'Random' NULL

Answer 1

This should do it.
SELECT YT.[Sample Data],
S2.[Output]
FROM YourTable YT
CROSS APPLY (SELECT 'Account #') S(S)
CROSS APPLY (SELECT CASE
WHEN CHARINDEX(S.S, [Sample Data]) > 0
THEN SUBSTRING([Sample Data], LEN(S.S) + CHARINDEX(S.S, [Sample Data]), 8000)
END) S1(StringWithNumberAtStart)
CROSS APPLY (SELECT LEFT(StringWithNumberAtStart,
PATINDEX('%[^0-9]%', StringWithNumberAtStart + 'X'))) S2([Output])

Answer 2

You might try this:
DECLARE #dummyTbl TABLE(YourString VARCHAR(100));
INSERT INTO #dummyTbl VALUES
('Account #12345')
,('Account #123456')
,('Random # note')
,('Account #1234567');
WITH Casted AS
(
SELECT YourString
,CAST('<x>' + REPLACE(YourString,' #','</x><x>') + '</x>' AS XML) toXML
FROM #dummyTbl
)
SELECT YourString
,toXML
,toXML.value('x[1]','nvarchar(max)') AS KeyText
,toXML.value('x[2] cast as xs:int?','int') AS NumberIfCastable
FROM Casted;
The result
YourString toXML KeyText NumberIfCastable
Account #12345 <x>Account</x><x>12345</x> Account 12345
Account #123456 <x>Account</x><x>123456</x> Account 123456
Random # note <x>Random</x><x> note</x> Random NULL
Account #1234567 <x>Account</x><x>1234567</x> Account 1234567
You can see, that I used a trick with CAST and REPLACE to transform your string to an XML which allows to address each part separately. The XPath to the first element x[1] returns Account or Random while the second x[2] returns the number.
A second trick I use is XQuerys implicit ability to try_cast a value. If the value cannot be converted to an xs:int? it will be returned as a NULL.

Answer 3

This ensures 5 digits after 'Account #' and ask for isnumeric when longer. This is not 100% your request but is an approach. Isnumeric function works in a special way
https://learn.microsoft.com/en-us/sql/t-sql/functions/isnumeric-transact-sql
--len('Account #') is 9
select case when Notes like 'Account #[0-9][0-9][0-9][0-9][0-9]%'
and isnumeric(right(Notes,len(Notes)-9) )=1 then right(Notes,len(Notes)-9)
else null end
from myTable
For SQLServer 2012+ use try_parse
https://learn.microsoft.com/en-us/sql/t-sql/functions/try-parse-transact-sql
select case when Notes like 'Account #[0-9][0-9][0-9][0-9][0-9]%'
and isnumeric(try_parse(right(Notes,len(Notes)-9) as bigint ))=1
then right(Notes,len(Notes)-9) else null end
from myTable
SQLFIDDLE http://sqlfiddle.com/#!6/cd617/2

Answer 4

I would use substring() with patindex() function to get the numeric values only
SELECT sampledata, SUBSTRING(sampledata, PATINDEX('%[1-9]%', SampleData),
case
when(LEN(sampledata)-PATINDEX('%[1-9]%', SampleData)+1) > LEN(SampleData)
then 0
else LEN(sampledata)-PATINDEX('%[1-9]%', SampleData)+1
end) numericvalues
FROM table;
EDIT:
Changing the question after you have asked it is rude. It can invalidate answers which in turn can attract down votes.
Well, i updated the answer according to the edited post.
select sampledata,
case
when patindex('%Account #%', sampledata) > 0
then SUBSTRING(sampledata, PATINDEX('%[1-9]%', sampledata), LEN(sampledata)-PATINDEX('%[1-9]%', sampledata)+1)
end [Output]
from table
Result :
Sample Data Output
'Account #12345' 12345
'Account #123456' 123456
'Random #12345' NULL
'Account #1234567' 1234567
'12345' NULL
'Random' NULL