Select INTO with binding parameters not working with execute immediate - oracle

Question

I have the following query that returns 1 when executed:
SELECT COUNT(*) FROM TABLE_NAME WHERE Column1='x' AND Column2='y';
In my PL/SQL block, I need to evaluate the condition above in order to execute the business logic. Below is a simplified version:
DECLARE
column1 VARCHAR(20):='x';
column2 VARCHAR(20):='y';
rows_no NUMBER :=0;
sql_query VARCHAR2(200) :='SELECT COUNT(*) FROM TABLE_NAME WHERE Column1=:1 AND Column2=:2';
BEGIN
EXECUTE IMMEDIATE sql_query INTO rows_no USING column1, column2;
DBMS_OUTPUT.PUT_LINE('ROWS NO: '|| rows_no);
END;
The result from the execution of the PL/SQL block is 0 that is different from the result when the query is executed that is 1. I think I abiding by the rules of the binding parameter to query select into in the PL/SQL. I will appreciate any help or guide.
Best Regards,
Rando.
P.S
When I make the modification below :
DECLARE
column1 VARCHAR(20):='x';
column2 VARCHAR(20):='y';
rows_no NUMBER :=0;
sql_query VARCHAR2(200) :='SELECT COUNT(*) FROM TABLE_NAME WHERE Column1=''x'' AND Column2=''y''';
BEGIN
EXECUTE IMMEDIATE sql_query INTO rows_no;
DBMS_OUTPUT.PUT_LINE('ROWS NO: '|| rows_no);
END;
The result is: 1
I have a loop that reads from an excel file and inserts it into the database table(Table_name). The result above is needed to prevent the insertion of dublicates records. The commit is issued at the end of the procedure.
That means that if a record is added from the procedure it remains uncommitted till the procedure finishes.
I doubt this is a problem, uncommitted inserts are not accessible from other connections but in the current connection, they should be accessible. The following has all the simplified logic of the plsql block:
DECLARE;
--declaration variables
BEGIN
LOOP
-- fetching information from excel file
EXECUTE IMMEDIATE sql_query INTO rows_no;
DBMS_OUTPUT.PUT_LINE('ROWS NO: '|| rows_no);
IF rows_no=0 THEN
-- insert the information read from excel in database table
rows_inserted:=rows_inserted+1;
END IF;
END LOOP;
IF rows_inserted>0 THEN
COMMIT;
DBMS_OUTPUT.PUT_LINE('ROWS INSERTED: '||rows_inserted);
ELSE
DBMS_OUTPUT.PUT_LINE('No rows were inserted');
END IF;
END

Answer 1

The problem is most probably outside from Oracle, please try to re-test following script
(The output is shown as comment)
create table tab (column1 varchar2(1), column2 varchar2(1));
set SERVEROUTPUT ON
DECLARE
column1 VARCHAR(20):='x';
column2 VARCHAR(20):='y';
rows_no NUMBER :=0;
sql_query VARCHAR2(200) :='SELECT COUNT(*) FROM TAB WHERE Column1=:1 AND Column2=:2';
BEGIN
EXECUTE IMMEDIATE sql_query INTO rows_no USING column1, column2;
DBMS_OUTPUT.PUT_LINE('ROWS NO: '|| rows_no);
END;
/
-- ROWS NO: 0
insert into tab (column1, column2) values ('x','y');
DECLARE
column1 VARCHAR(20):='x';
column2 VARCHAR(20):='y';
rows_no NUMBER :=0;
sql_query VARCHAR2(200) :='SELECT COUNT(*) FROM TAB WHERE Column1=:1 AND Column2=:2';
BEGIN
EXECUTE IMMEDIATE sql_query INTO rows_no USING column1, column2;
DBMS_OUTPUT.PUT_LINE('ROWS NO: '|| rows_no);
END;
/
-- ROWS NO: 1