Convert T-SQL function to PL/SQL [duplicate] - sql-server

Question

This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
How to best split csv strings in oracle 9i
can you help me convert following T-SQL funcntion into Oracle. The function converts a string like
service|nvretail;language|de;yyyy|2011;
to a table.
The main problem I have is the usage of the temp table. I could not find any equivalent to it in Oracle.
CREATE FUNCTION [dbo].[TF_ConvertPara]
(
#parastringNVARCHAR(max)
)
RETURNS #para TABLE
(
[Key] varchar(max),
[Value] varchar(max)
)
begin
DECLARE #NextString NVARCHAR(40)
DECLARE #Pos1 INT
DECLARE #Pos2 INT
DECLARE #NextPos INT
DECLARE #Delimiter1 NCHAR=';'
DECLARE #Delimiter2 NCHAR='|'
if substring(#paraString, len(#paraString) - 1, 1) <> #Delimiter1
SET #paraString = #paraString + #Delimiter1
SET #Pos1 = charindex(#Delimiter1, #paraString)
WHILE (#pos1 <> 0)
BEGIN
SET #NextString = substring(#paraString, 1, #Pos1 - 1)
SET #paraString = substring(#paraString, #pos1 + 1, len(#paraString))
SET #pos1 = charindex(#Delimiter1, #paraString)
SET #Pos2 = charindex(#Delimiter2, #NextString)
if (#Pos2 > 0)
begin
insert into #para
values
(substring(#NextString, 1, #Pos2 - 1),
substring(#NextString, #Pos2 + 1, len(#NextString)))
end
END
return;
end
Thank you in advance.

Answer 1

If you are looking to return the tokens of your string as rows then you could do it all in a single SQL query:
WITH t AS (SELECT 'service|nvretail;language|de;yyyy|2011;' as val FROM dual)
SELECT row_output
FROM t,
XMLTABLE( '/root/e/text()'
PASSING xmltype( '<root><e>' ||
REGEXP_REPLACE (t.val, '(;|\|)', '</e><e>' ) ||
'</e></root>' )
COLUMNS row_output VARCHAR2( 4000 ) PATH '/');
Returns:
service
nvretail
language
de
yyyy
2011
If you want these rows in a table then wrap the SQL in a simple function to either return the in-memory table or insert the records into a DB table, whichever you need.
Here is an example of a function returning a table (collection) of VARCHAR2 records:
CREATE OR REPLACE
FUNCTION str_to_table (
p_input_str IN VARCHAR2
)
RETURN DBMS_SQL.VARCHAR2_TABLE
IS
CURSOR str_to_rows (
cp_str IN VARCHAR2
)
IS
SELECT row_output
FROM (SELECT cp_str as val FROM dual) t,
XMLTABLE( '/root/e/text()'
PASSING xmltype( '<root><e>' ||
REGEXP_REPLACE(t.val, '(;|\|)', '</e><e>') ||
'</e></root>' )
COLUMNS row_output VARCHAR2( 4000 ) PATH '/');
varchar_tab DBMS_SQL.VARCHAR2_TABLE;
BEGIN
OPEN str_to_rows(p_input_str);
FETCH str_to_rows BULK COLLECT INTO varchar_tab;
CLOSE str_to_rows;
--
RETURN varchar_tab;
EXCEPTION
WHEN others
THEN
IF str_to_rows%ISOPEN
THEN
CLOSE str_to_rows;
END IF;
RAISE;
END str_to_table;
It's untested so there may be a couple of syntax errors but it should be prety close.
To return a ref cursor:
CREATE OR REPLACE
FUNCTION str_to_table (
p_input_str IN VARCHAR2
)
RETURN sys_refcursor
IS
cur SYS_REFCURSOR;
BEGIN
OPEN cur
FOR SELECT row_output
FROM (SELECT p_input_str as val FROM dual) t,
XMLTABLE( '/root/e/text()'
PASSING xmltype( '<root><e>' ||
REGEXP_REPLACE (t.val, '(;|\|)', '</e><e>' ) ||
'</e></root>' )
COLUMNS row_output VARCHAR2( 4000 ) PATH '/');
--
RETURN cur;
END str_to_table;
Hope it helps...

Answer 2

To return the key value pairs, How about this (for Oracle 10g and above):
CREATE OR REPLACE FUNCTION csv_to_rows(mycsv IN VARCHAR2)
RETURN sys_refcursor
AS
c SYS_REFCURSOR;
BEGIN
OPEN c FOR
SELECT SUBSTR(element,1,INSTR(element,'|')-1) as key ,
SUBSTR(element,INSTR(element,'|')+1,99999) as val
FROM (
SELECT REGEXP_SUBSTR(mycsv,'[^;]+',1,LEVEL) element
FROM dual
CONNECT BY LEVEL < LENGTH(REGEXP_REPLACE(mycsv,'[^;]+')) + 1
);
RETURN c;
END;
and to see your results:
DECLARE
c SYS_REFCURSOR;
akey VARCHAR2(100);
aval VARCHAR2(100);
BEGIN
c := csv_to_rows('service|nvretail;language|de;yyyy|2011');
LOOP
FETCH c into akey,aval;
EXIT WHEN c%NOTFOUND;
dbms_output.put_line('Key : '||akey || ' Value : '||aval);
END LOOP;
END;
this should give you
Key : service Value : nvretail
Key : language Value : de
Key : yyyy Value : 2011