SQL - String Manipulation - sql-server

Question

Context:
I have a view in SQL Server that tracks parameters a user inputs when they run an SSRS report (ReportServer.dbo.ExecutionLog). About 50 report parameters are saved as a string in a single column with ntext datatype. I would like to break this single column up into multiple columns for each parameter.
Details:
I query the report parameters like this:
SELECT ReportID, [Parameters]
FROM ReportServer.dbo.ExecutionLog
WHERE ReportID in (N'redacted')
and [Status] in (N'rsSuccess')
ORDER BY TimeEnd DESC
And here's a small subset of what the results look like:
alpha=123&bravo=9%2C33%2C76%2C23&charlie=91&delta=29&echo=11%2F2%2F2018%2012%3A00%3A00%20AM&foxtrot=11%2F1%2F2030%2012%3A00%3A00%20AM
Quesitons:
How can I get the results to look like this:
SQL Server 2017 is Python friendly. Is Python a better language to use in this scenario just for parsing purposes?
I've seen similar topics posted here, here & here. The parameters are dynamic so parsing via SQL string functions that involve counting characters doesn't apply. This question is relevant to more people than just me because there's a large population of people using SSRS. Tracking & formatting parameters in a more digestible way is valuable for all users of SSRS.

Answer 1

Here is a way using the built in STRING_SPLIT. I'm just not sure what the logic is for the stuff AFTER the date, so I would discarded it but I left it for you to decide.
DEMO
declare #table table (ReportID int identity(1,1), [Parameters] varchar(8000))
insert into #table
values
('alpha=123&bravo=9%2C33%2C76%2C23&charlie=91&delta=29&echo=11%2F2%2F2018%2012%3A00%3A00%20AM&foxtrot=11%2F1%2F2030%2012%3A00%3A00%20AM')
,('alpha=457893&bravo=9%2C33%2C76%2C23&charlie=91&delta=29&echo=11%2F2%2F2018%2012%3A00%3A00%20AM&foxtrot=11%2F1%2F2030%2012%3A00%3A00%20AM')
select
ReportID
,[Parameters]
,alpha = max(iif(value like 'alpha%',substring(value,charindex('=',value) + 1,99),null))
,bravo = max(iif(value like 'bravo%',substring(value,charindex('=',value) + 1,99),null))
,charlie = max(iif(value like 'charlie%',substring(value,charindex('=',value) + 1,99),null))
,delta = max(iif(value like 'delta%',substring(value,charindex('=',value) + 1,99),null))
,echo = max(iif(value like 'echo%',substring(value,charindex('=',value) + 1,99),null))
,foxtrot = max(iif(value like 'foxtrot%',substring(value,charindex('=',value) + 1,99),null))
from #table
cross apply string_split(replace(replace([Parameters],'%2C',','),'%2F','/'),'&')
group by ReportID, [Parameters]
Or, if they aren't static you can use a dynamic pivot. It'll take some massaging to get your columns in the correct order.
DEMO
DECLARE #cols AS NVARCHAR(MAX),
#query AS NVARCHAR(MAX);
SET #cols = STUFF((SELECT distinct ',' + QUOTENAME(substring([value],0,charindex('=',[value])))
from myTable
cross apply string_split(replace(replace([Parameters],'%2C',','),'%2F','/'),'&')
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
select #cols
set #query = 'SELECT ReportID, ' + #cols + ' from
(
select ReportID
, ColName = substring([value],0,charindex(''='',[value]))
, ColVal = substring([value],charindex(''='',[value]) + 1,99)
from myTable
cross apply string_split(replace(replace([Parameters],''%2C'','',''),''%2F'',''/''),''&'')
) x
pivot
(
max(ColVal)
for ColName in (' + #cols + ')
) p '
execute(#query)

Answer 2

Split the string on the ampersand character.
Further split each row into two columns on the equals character.
In the second column, replace %2C with the comma character, and %2F with the forward-slash character, and so on with any other replacements as needed.
Use a dynamic-pivot to query the above in the format that you want.

Answer 3

Here's a method that starts with a lot of replaces.
To url-decode the string and transform it into an XML type.
Then it uses the XML functions to get the values for the columns.
Example snippet:
declare #Table table ([Parameters] varchar(200));
insert into #Table ([Parameters]) values
('alpha=123&bravo=9%2C33%2C76%2C23&charlie=91&delta=29&echo=11%2F2%2F2018%2012%3A00%3A00%20AM&foxtrot=11%2F1%2F2030%2012%3A00%3A00%20AM');
select
x.query('/x[key="alpha"]/val').value('.', 'int') as alpha,
x.query('/x[key="bravo"]/val').value('.', 'varchar(30)') as bravo,
x.query('/x[key="charlie"]/val').value('.', 'varchar(30)') as charlie,
x.query('/x[key="delta"]/val').value('.', 'varchar(30)') as delta,
convert(date, x.query('/x[key="echo"]/val').value('.', 'varchar(30)'), 103)as echo,
convert(date, x.query('/x[key="foxtrot"]/val').value('.', 'varchar(30)'), 103) as foxtrot
from #Table
cross apply (select cast('<x><key>'+
replace(replace(replace(replace(replace(
replace([Parameters],
'%2C',','),
'%2F','/'),
'%20',' '),
'%3A',':'),
'=','</key><val>'),
'&','</val></x><x><key>')
+'</val></x>' as XML) as x) ca
Test on db<>fiddle here