How to execute the packaged procedure

Question

Hello i've written the following package: It's created fine but while running that procedure i'm getting the following error
create or replace package ttt_example as
  TYPE ColumnsInfo IS RECORD (
      columnName VARCHAR2 (30),
      dataType VARCHAR2 (30)
TYPE ColumnsInfoList IS TABLE OF ColumnsInfo; 
FUNCTION getColumns (
      schemaName VARCHAR2,
      tableName VARCHAR2
      RETURN ColumnsInfoList;
PROCEDURE fillTable (
      schemaName VARCHAR2,
      tableName VARCHAR2
end;
create or replace package body ttt_example is
PROCEDURE fillTable (
      schemaName VARCHAR2,
      tableName VARCHAR2
   ) IS
      i NUMBER;
      columnsList ColumnsInfoList;
      columnsStr VARCHAR2 (4000);
      valList VARCHAR2 (4000) := NULL;
      insertTime VARCHAR2 (100);
   BEGIN
      DBMS_OUTPUT.PUT_LINE ('fillTable - BEGIN');
      columnsList := getColumns (schemaName, tableName);
      i := columnsList.FIRST;
      IF i IS NOT NULL THEN
         columnsStr := columnsList (i).columnName;
         i := columnsList.NEXT (i);
      END IF;
      WHILE i IS NOT NULL LOOP
         columnsStr := columnsStr || ', ' || columnsList (i).columnName;
         i := columnsList.NEXT (i);
      END LOOP;
      i := columnsList.FIRST;
      WHILE i IS NOT NULL LOOP
         IF i != columnsList.LAST THEN
            IF columnsList (i).dataType = 'NUMBER' THEN
               valList := valList || i || ', ';
            ELSIF columnsList (i).dataType = 'VARCHAR2' THEN
               valList := valList || '''' || i || '''' || ', ';
            ELSIF columnsList (i).dataType = 'DATE' THEN
               --EXECUTE IMMEDIATE 'SELECT TO_CHAR(SYSTIMESTAMP) FROM dual' INTO insertTime;
               --valList := valList ||''''|| insertTime||''''|| ', ';
               valList := valList || 'SYSDATE, ';
            ELSE
               DBMS_OUTPUT.PUT_LINE ('WRONG DATA TYPE ' || columnsList (i).dataType);
            END IF;
         ELSE
            IF columnsList (i).dataType = 'NUMBER' THEN
               valList := valList || i;
            ELSIF columnsList (i).dataType = 'VARCHAR2' THEN
               valList := valList || '''' || i || '''';
            ELSIF columnsList (i).dataType = 'DATE' THEN
               --EXECUTE IMMEDIATE 'SELECT TO_CHAR(SYSTIMESTAMP) FROM dual' INTO insertTime;
               --valList := valList ||''''|| insertTime||'''';
               valList := valList || 'SYSDATE';
            ELSE
               DBMS_OUTPUT.PUT_LINE ('WRONG DATA TYPE ' || columnsList (i).dataType);
            END IF;
         END IF;
         i := columnsList.NEXT (i);
      END LOOP;
      DBMS_OUTPUT.PUT_LINE ('fillTable - MIDDLE');
      EXECUTE IMMEDIATE 'INSERT INTO ' || tableName || '(' || columnsStr || ') VALUES (' || valList || ')';
      DBMS_OUTPUT.PUT_LINE ('fillTable - END');
   END;
FUNCTION getColumns (
      schemaName VARCHAR2,
      tableName VARCHAR2
      RETURN ColumnsInfoList IS
      columnsList ColumnsInfoList;
   BEGIN
      DBMS_OUTPUT.PUT_LINE ('getColumns - BEGIN');
      EXECUTE IMMEDIATE 'SELECT COLUMN_NAME, DATA_TYPE FROM ALL_TAB_COLUMNS WHERE OWNER = ''' || schemaName || ''' AND TABLE_NAME = ''' || tableName || ''''
      BULK COLLECT INTO columnsList;
      DBMS_OUTPUT.PUT_LINE ('getColumns - END');
      RETURN columnsList;
   EXCEPTION
      WHEN OTHERS THEN
                  RAISE;
   END;
end;
/  While executing that package procedure
SQL> begin
  2  ttt_example.fillTable('TEST','EMPE');
  3  end;
  4  /
begin
ERROR at line 1:
ORA-00928: missing SELECT keyword
ORA-06512: at "ttt.TTT_EXAMPLE", line 60
ORA-06512: at line 2help me in this

Answer 1

I was able to reproduce with NULL for columnstr;
create table t (c1 varchar2(20), c2 varchar2(20));
Table created
create or replace procedure p
  tablename  varchar2,
  columnsstr varchar2,
  vallist    varchar2
) is
begin
  execute immediate 'INSERT INTO ' || tablename || '(' || columnsstr ||
                    ') VALUES (' || vallist || ')';
end;
Procedure created
exec p('t', 'c1,c2', '''a'',''b''');
PL/SQL procedure successfully completed
select * from t;
C1                   C2
a                    b
exec p('t', '', '''a'',''b''');
begin p('t', '', '''a'',''b'''); end;
ORA-00928: missing SELECT keyword
ORA-06512: at "MSCALLION.P", line 8
ORA-06512: at line 2