Oracle Parse NCLOB data to Output or New Table - sql

Question

I have an Oracle 11.2.0.4.0 table named LOOKUPTABLE with 3 fields
LOOKUPTABLEID NUMBER(12)
LOOKUPTABLENM NVARCHAR2(255)
LOOKUPTABLECONTENT NCLOB
The data in the NCLOB field is highly validated on insert so I'm certain the data always is a comma separated string with a CRLF on the end so reads exactly like a simple CSV file. Example ([CRLF] is representation of an actual CRLF, not text)
WITH lookuptable AS (
SELECT
1 AS "LOOKUPTABLEID",
'CODES.TBL' AS "LOOKUPTABLENM",
TO_NCLOB('851,ALL HOURS WORKED GLASS,G,0,,,,,,'||chr(10)||chr(13)||
'935,ALL OT AND HW HRS,G,0,,,,,,'||chr(10)||chr(13)||
'934,ALL PAID TIME,G,0,,,,,,'||chr(10)||chr(13)) AS "LOOKUPTABLECONTENT"
FROM dual
)
SELECT lookuptablecontent FROM lookuptable WHERE lookuptablenm='CODES.TBL';
"851,ALL HOURS WORKED GLASS,G,0,,,,,,[CRLF]935,ALL OT AND HW HRS,G,0,,,,,,[CRLF]934,ALL PAID TIME,G,0,,,,,,[CRLF]"
I essentially want to have a query that can output 1 row for each line in the CLOB. I'm using an application that will read this SQL and write it to a text file for me but it cannot handle CLOB data types and I don't have the option to write directly to file from SQL itself. I have to have a query that can produce this result and allow my app to write the file. I do have the ability to create/write my own tables so a procedure that would read the CLOB into a new table and then I would select from that table in my application would be acceptable if that's better, its just over my head right now. Desired output below, thanks in advance for any help :)
1. 851,ALL HOURS WORKED GLASS,G,0,,,,,,
2. 935,ALL OT AND HW HRS,G,0,,,,,,
3. 934,ALL PAID TIME,G,0,,,,,,

Answer 1

This is a specific case of a general question "how to split a string", and I link this question a lot for more details on that. In this case, instead of a comma, the delimiter that you want to split on is CRLF, or chr(10)||chr(13).
Here's a simple solution with regexp_substr. It's not the fastest solution, but it works fine in simple scenarios. If you need better performance, see the version in the link above with a recursive CTE and no regexp.
WITH lookuptable AS (
SELECT
1 AS LOOKUPTABLEID,
'CODES.TBL' AS LOOKUPTABLENM,
TO_NCLOB('851,ALL HOURS WORKED GLASS,G,0,,,,,,'||chr(10)||chr(13)||
'935,ALL OT AND HW HRS,G,0,,,,,,'||chr(10)||chr(13)||
'934,ALL PAID TIME,G,0,,,,,,'||chr(10)||chr(13)) AS LOOKUPTABLECONTENT
FROM dual
)
SELECT lookuptableid as id, to_char(regexp_substr(lookuptablecontent,'[^('||chr(13)||chr(10)||')]+', 1, level))
FROM lookuptable
WHERE lookuptablenm='CODES.TBL'
connect by level <= regexp_count(lookuptablecontent, '[^('||chr(13)||chr(10)||')]+')
and PRIOR lookuptableid = lookuptableid and PRIOR SYS_GUID() is not null -- needed if more than 1 source row
order by lookuptableid, level
;
Output:
id r
1 851,ALL HOURS WORKED GLASS,G,0,,,,,,
1 935,ALL OT AND HW HRS,G,0,,,,,,
1 934,ALL PAID TIME,G,0,,,,,,

Answer 2

My example data and format using the recursive CTE without regexp from link provided by #kfinity
WITH lookuptable (lookuptableid, lookuptablenm, lookuptablecontent) AS (
SELECT
1,
'CODES.TBL',
TO_NCLOB('ID,NAME,TYPE,ISMONEYSW,EARNTYPE,EARNCODE,RATESW,NEGATIVESW,OVERRIDEID,DAILYSW'||chr(13)||chr(10)||
'851,ALL HOURS WORKED GLASS,G,0,,,,,,'||chr(13)||chr(10)||
'935,ALL OT AND HW HRS,G,0,,,,,,'||chr(13)||chr(10)||
'934,ALL PAID TIME,G,0,,,,,,'
)
FROM dual
), CTE (lookuptableid, lookuptablenm, lookuptablecontent, startposition, endposition) AS (
SELECT
lookuptableid,
lookuptablenm,
lookuptablecontent,
1,
INSTR(lookuptablecontent, chr(13)||chr(10))
FROM lookuptable
WHERE lookuptablenm = 'CODES.TBL'
UNION ALL
SELECT
lookuptableid,
lookuptablenm,
lookuptablecontent,
endposition + 1,
INSTR(lookuptablecontent, chr(13)||chr(10), endposition+1)
FROM CTE
WHERE endposition > 0
)
SELECT
lookuptableid,
lookuptablenm,
SUBSTR(lookuptablecontent, startposition, DECODE(endposition, 0, LENGTH(lookuptablecontent) + 1, endposition) - startposition) AS lookuptablecontent
FROM CTE
ORDER BY lookuptableid, startposition;