Flow does not enter in the loop - oracle

Question

Below is a PL/SQL. The problem is that the flow does not enter loop. I am unable to figure out what is the problem. Both the queries return results, i.e the query in the loop and the query within the loop does return results.
DECLARE
p_file_name VARCHAR2(4000) :='GHCPExtract_100_005_2011052218000700.csv';
v_file_name VARCHAR2(4000) :='' || '''' || p_file_name ||'''';
v_count NUMBER :=0;
v_loop NUMBER :=0;
begin
DBMS_OUTPUT.PUT_LINE( 'BEFORE LOOP');
FOR C IN (
SELECT
S.SOURCE_TRX_KEY_SEGMENT1 ,
S.SOURCE_TRX_KEY_SEGMENT2 ,
S.SOURCE_TRX_KEY_SEGMENT3 ,
S.SOURCE_TRX_KEY_SEGMENT4 ,
S.SOURCE_TRX_KEY_SEGMENT5 ,
S.SOURCE_TRX_KEY_SEGMENT6
FROM DM_RS.STG_GHCP_EXTRACT S
WHERE S.SOURCE_FILE_NAME = v_file_name
)
LOOP
DBMS_OUTPUT.PUT_LINE( 'IN LOOP');
BEGIN
select
1
into
v_count
from
(
select
T.SOURCE_TRX_KEY_SEGMENT1 ,
T.SOURCE_TRX_KEY_SEGMENT2 ,
T.SOURCE_TRX_KEY_SEGMENT3 ,
T.SOURCE_TRX_KEY_SEGMENT4 ,
T.SOURCE_TRX_KEY_SEGMENT5 ,
T.SOURCE_TRX_KEY_SEGMENT6
from
GTT_SEGMENT_ID t
WHERE 1=1
AND
T.SOURCE_TRX_KEY_SEGMENT1 = C.SOURCE_TRX_KEY_SEGMENT1
and
T.SOURCE_TRX_KEY_SEGMENT2 = C.SOURCE_TRX_KEY_SEGMENT2
and
T.SOURCE_TRX_KEY_SEGMENT3 = C.SOURCE_TRX_KEY_SEGMENT3
and
T.SOURCE_TRX_KEY_SEGMENT4 = C.SOURCE_TRX_KEY_SEGMENT4
and
T.SOURCE_TRX_KEY_SEGMENT5 = C.SOURCE_TRX_KEY_SEGMENT5
and
T.SOURCE_TRX_KEY_SEGMENT6 = C.SOURCE_TRX_KEY_SEGMENT6
and t.source_file_name = v_file_name
);
EXCEPTION
WHEN NO_DATA_FOUND THEN
v_count := 0;
END;
IF (v_count = 1)
THEN
V_LOOP := V_LOOP +1;
END IF;
END LOOP;
DBMS_OUTPUT.PUT_LINE( V_LOOP);
END;
DBMS_OUTPUT
BEFORE LOOP
0

Answer 1

v_file_name VARCHAR2(4000) :='' || '''' || p_file_name ||'''';
....
WHERE S.SOURCE_FILE_NAME = '' || '''' || v_file_name ||''''
How many quotes contain SOURCE_FILE_NAME in table?
You can check count rows in query using temporary variable -
SELECT count(1)
INTO cnt_
FROM DM_RS.STG_GHCP_EXTRACT S
WHERE S.SOURCE_FILE_NAME = '''' || v_file_name ||'''';
DBMS_OUTPUT.put_line('rows count: '||cnt_);
Also, check that data in table commited and available in other session.
EDIT:
It's obvious that query in cycle returns no rows, because 'IN LOOP' doesn't printed in output.
How many rows return this query? -
SELECT count(1)
FROM dm_rs.stg_ghcp_extract s
WHERE s.source_file_name = '' || '''' || 'GHCPExtract_100_005_2011052218000700.csv' || ''''
Btw, if you need only count of compared rows you can use one select with EXISTS instead of cycle.
SELECT count(1)
into v_count
FROM dm_rs.stg_ghcp_extract c
WHERE c.source_file_name = v_file_name
AND EXISTS
(SELECT 1
FROM gtt_segment_id t
WHERE t.source_trx_key_segment1 = c.source_trx_key_segment1
AND t.source_trx_key_segment2 = c.source_trx_key_segment2
AND t.source_trx_key_segment3 = c.source_trx_key_segment3
AND t.source_trx_key_segment4 = c.source_trx_key_segment4
AND t.source_trx_key_segment5 = c.source_trx_key_segment5
AND t.source_trx_key_segment6 = c.source_trx_key_segment6
AND t.source_file_name = c.source_file_name)