Finding line and position of text in string - sql

Question

I need to get de line number and position (on that line) of a specific word in a text.
For example:
--
This is my first line.
This is my second line.
--
If I would check for 'second' I should get something back like: 2,12
Anyone any suggestion?

Answer 1

Assuming you are looking for the first occurrence per line, and assuming a LINE is delimited by char(13) and not punctuation.
Example
Declare #YourTable table (ID int,SomeText varchar(max))
Insert Into #YourTable values
(1,'This is my first line.
This is my second line.')
,(2,'This another but has a second note
Which not related to the prior "second" note')
Declare #Search varchar(100)='second'
Select A.ID
,Position=concat(RetSeq,',',charindex(#Search,RetVal))
From #YourTable A
Cross Apply (
Select RetSeq = row_number() over (order by 1/0)
,RetVal = ltrim(rtrim(B.i.value('(./text())[1]', 'varchar(max)')))
From (Select x = Cast('<x>' + replace((Select replace(replace(SomeText,char(10),''),char(13),'§§Split§§') as [*] For XML Path('')),'§§Split§§','</x><x>')+'</x>' as xml).query('.')) as A
Cross Apply x.nodes('x') AS B(i)
) B
Where charindex(#Search,RetVal)>0
Returns
ID Position
1 2,12
2 1,24
2 2,33
EDIT - Requested EDIT
Select Top 1 with Ties
A.ID
,Position=concat(RetSeq,',',charindex(#Search,RetVal))
From #YourTable A
Cross Apply (
Select RetSeq = row_number() over (order by 1/0)
,RetVal = B.i.value('(./text())[1]', 'varchar(max)')
From (Select x = Cast('<x>' + replace((Select replace(replace(SomeText,char(10),''),char(13),'§§Split§§') as [*] For XML Path('')),'§§Split§§','</x><x>')+'</x>' as xml).query('.')) as A
Cross Apply x.nodes('x') AS B(i)
) B
Where charindex(#Search,RetVal)>0
Order by Row_Number() over (Partition By ID Order by RetSeq)
Returns
ID Position
1 2,12
2 1,24

Answer 2

Here is an alternative solution that does not make use of a subquery ; it relies on ,SQL Server string functions, such as CHARINDEX and REVERSE.
SELECT
CASE WHEN CHARINDEX( #match, t.value ) < CHARINDEX( CHAR(10), t.value )
THEN CONCAT( '1,', CHARINDEX( #match, t.value ) )
ELSE
CONCAT(
LEN(LEFT(t.value, CHARINDEX(#match, t.value)))
- LEN(REPLACE(LEFT(t.value, CHARINDEX(#match, t.value)), CHAR(10), '')) + 1,
',',
CHARINDEX (CHAR(10), REVERSE(LEFT(t.value, CHARINDEX(#match, t.value)))) - 1
)
END
from t;
The principle is to first find the position of the searched string (#match), and then compute the position of the previous carriage return (CHAR(10) - could be also CHAR(13) depending on your EOF settings), using REVERSE. With these two values at hand, we can compute the position of the match on the line, and the line number (for this, we compare the length of the substring until the match to its length without carriage returns). Special care has to be taken when the match is on the first line.
db<>fiddle here
Declare #match varchar(100) = 'second';
with t as (SELECT 'This is my first line.
This is my second line.
This is my third line.' value)
SELECT
CASE WHEN CHARINDEX( #match, t.value ) < CHARINDEX( CHAR(10), t.value )
THEN CONCAT( '1,', CHARINDEX( #match, t.value ) )
ELSE
CONCAT(
LEN(LEFT(t.value, CHARINDEX(#match, t.value)))
- LEN(REPLACE(LEFT(t.value, CHARINDEX(#match, t.value)), CHAR(10), '')) + 1,
',',
CHARINDEX (CHAR(10), REVERSE(LEFT(t.value, CHARINDEX(#match, t.value)))) - 1
)
END
from t;
GO
| (No column name) |
| :--------------- |
| 2,12 |