Extract string using SQL Server 2012 - sql

Question

I have a string in the form of
<div>#FIRST#12345#</div>
How do I extract the number part from this string using T-SQL in SQL Server 2012? Note the number has variable length

Answer 1

Using just t-sql string functions you can try:
create table t(col varchar(50))
insert into t select '<div>#FIRST#12345#</div>'
insert into t select '<div>#THIRD#543#</div>'
insert into t select '<div>#SECOND#3690123#</div>'
select col,
case when p1.v=0 or p2.v <= p1.v then ''
else Substring(col, p1.v, p2.v-p1.v)
end ExtractedNumber
from t
cross apply(values(CharIndex('#',col,7) + 1))p1(v)
cross apply(values(CharIndex('#',col, p1.v + 1)))p2(v)
Output:
Caveat, this doesn't handle any "edge" cases and assumes data is as described.

Answer 2

Shooting from the hip due to a missing minimal reproducible example.
Assuming that it is XML data type column.
SQL
-- DDL and sample data population, start
DECLARE #tbl TABLE (ID INT IDENTITY PRIMARY KEY, xmldata XML);
INSERT INTO #tbl (xmldata) VALUES
('<div>#FIRST#12345#</div>'),
('<div>#FIRST#770770#</div>');
-- DDL and sample data population, end
SELECT t.*
, LEFT(x, CHARINDEX('#', x) - 1) AS Result
FROM #tbl t
CROSS APPLY xmldata.nodes('/div/text()') AS t1(c)
CROSS APPLY (SELECT REPLACE(c.value('.', 'VARCHAR(100)'), '#FIRST#' ,'')) AS t2(x);
Output
+----+---------------------------+--------+
| ID | xmldata | Result |
+----+---------------------------+--------+
| 1 | <div>#FIRST#12345#</div> | 12345 |
| 2 | <div>#FIRST#770770#</div> | 770770 |
+----+---------------------------+--------+