Dynamic query and parameters

Question

Hi there,
I have created a procedure and passing values via parameters but then the sql statement takes it as a string rather than parameters. Could you please let me know what it is that I am doing wrong.
Code is as follows:
CREATE OR REPLACE FUNCTION GetTableData(p_vInTname IN VARCHAR2
  ,p_dInLastPubTms IN DATE
RETURN CLOB
IS
  vStrSqlQuery VARCHAR2(32767);
  TYPE ref_cursor IS REF CURSOR;
  rc_tablevalues ref_cursor;
  lc_XML CLOB;
BEGIN
  vStrSqlQuery:= q'[SELECT dbms_xmlgen.getxml('SELECT * FROM p_vInTname ' ||' WHERE record_update_tms >= TO_DATE(p_dInLastPubTMS,'MM/DD/YYYY HH24:MI:SS')) FROM dual]';
  DBMS_OUTPUT.put_line(vStrSqlQuery);
  OPEN rc_tablevalues FOR vStrSqlQuery;
  FETCH rc_tablevalues INTO lc_XML;
  CLOSE rc_tablevalues;
  RETURN lc_XML;
  printClob(lc_XML);
END GetTableData;
This compiled successfully.
Another procedure for printing
Create or replace PROCEDURE printClob (result IN OUT NOCOPY CLOB) IS
    xmlstr   VARCHAR2 (32767);
    line     VARCHAR2 (2000);
  BEGIN
    xmlstr := DBMS_LOB.SUBSTR (result, 32767);
    LOOP
       EXIT WHEN xmlstr IS NULL;
       line := SUBSTR (xmlstr, 1, INSTR (xmlstr, CHR (10)) - 1);
       DBMS_OUTPUT.put_line ('| ' || line);
       xmlstr := SUBSTR (xmlstr, INSTR (xmlstr, CHR (10)) + 1);
    END LOOP;
  END printClob;
I am trying to test it to see how it behaves, so created a test procedure which is:
CREATE OR REPLACE PROCEDURE SANDEEP_TEST_LAMXML
IS
lv_x CLOB;
BEGIN
  lv_x := CTN_PUB_CNTL_EXTRACT_PUBLISH.GetTableData('TRKFCG_SBDVSN',TO_DATE('04/27/2015 19:57:10', 'MM/DD/YYYY HH24:MI:SS'));
END;
The above one too compiles successfully. However when I set a break point and then try to pass through the function instead of seeing the parameter in the second part of the query, I am seeing it as:
SELECT dbms_xmlgen.getxml('SELECT * FROM p_vInTname ' ||' WHERE record_update_tms >= TO_DATE(p_dInLastPubTMS,'MM/DD/YYYY HH24:MI:SS')) FROM dual
What is that I am doing wrong that I am unable to see the runtime parameters being passed into the variables of the query? Can any one suggest something? I am handling dynamic queries and also a solution such as the above for the first time.
Thanks in advance.

Answer 1

There are quite a few errors and here's a working version:
CREATE OR REPLACE FUNCTION GetTableData(p_vInTname IN VARCHAR2
  ,p_dInLastPubTms IN VARCHAR2
RETURN CLOB
IS
  vStrSqlQuery VARCHAR2(32767);
  TYPE ref_cursor IS REF CURSOR;
  rc_tablevalues ref_cursor;
  lc_XML CLOB;
BEGIN 
  vStrSqlQuery:= q'[SELECT dbms_xmlgen.getxml('SELECT * FROM ]'||p_vInTname||q'[ WHERE record_update_tms >= TO_DATE('']'||p_dInLastPubTMS||q'['',''MM/DD/YYYY HH24:MI:SS'')') FROM dual]';
  DBMS_OUTPUT.put_line(vStrSqlQuery);
  OPEN rc_tablevalues FOR vStrSqlQuery;
  FETCH rc_tablevalues INTO lc_XML;
  CLOSE rc_tablevalues;
  printClob(lc_XML);
  RETURN lc_XML;
END GetTableData;
CREATE OR REPLACE PROCEDURE SANDEEP_TEST_LAMXML
IS
lv_x CLOB;
BEGIN
  lv_x := GetTableData('TRKFCG_SBDVSN','04/27/2015 19:57:10');
END;
This version will be easier to understand:
CREATE OR REPLACE FUNCTION GetTableData(p_vInTname IN VARCHAR2 
  ,p_dInLastPubTms IN VARCHAR2 
RETURN CLOB 
IS 
  vStrSqlQuery VARCHAR2(32767); 
  TYPE ref_cursor IS REF CURSOR; 
  rc_tablevalues ref_cursor; 
  lc_XML CLOB; 
BEGIN  
  vStrSqlQuery:= 'SELECT * FROM '||p_vInTname||' WHERE record_update_tms >= TO_DATE('''||p_dInLastPubTMS||''',''MM/DD/YYYY HH24:MI:SS'')';
  DBMS_OUTPUT.put_line(vStrSqlQuery); 
SELECT dbms_xmlgen.getxml(vStrSqlQuery)
  INTO lc_XML
  FROM dual;
  printClob(lc_XML); 
  RETURN lc_XML; 
END GetTableData;