title: Why I get error message "Invalid number" since UserID is NUMBER
body: <p>I am little bit confusing and have no idea where I made mistake.</p>
  <pre><code>SELECT uta.StartDate, uta.EndDate FROM user_timesheets_absence uta
  WHERE uta.UserID = 353
  AND uta.Approved = 'true'
  AND '2020-03-06' BETWEEN TO_DATE(uta.StartDate,'YYYY-MM-DD') AND TO_DATE(uta.EndDate,'YYYY-MM-DD') + INTERVAL '1' DAY
  </code></pre>
  <p>In following query I get error</p>
  <pre><code>ORA-01722: invalid number
  </code></pre>
  <p>I try to understand where the error is, but when I realize query a deeper I can not see where the error is.</p>
  <pre><code>ABSENCETYPE VARCHAR2(255 CHAR)
  ANSWER  VARCHAR2(500 CHAR)
  APPROVED    NUMBER(10,0)
  COMMENT_    CLOB
  DAYS    NUMBER(10,0)
  ENDDATE VARCHAR2(50 CHAR)
  ISANSWERED  NUMBER(10,0)
  ISREJECTED  NUMBER(10,0)
  STARTDATE   VARCHAR2(50 CHAR)
  USERABSENCEID   NUMBER(10,0)
  USERHASSEEN VARCHAR2(500 CHAR)
  USERID  NUMBER(10,0)
  WIDTH   NUMBER(10,0)
  </code></pre>
  <p>When I insert data into table, I use this kind of data and It works fine. But when I use SELECT statment I get error. I hope the error was UserID but it wasn't.</p>
  <pre><code>Insert into DB.USER_TIMESHEETS_ABSENCE (ABSENCETYPE,ANSWER,APPROVED,DAYS,ENDDATE,ISANSWERED,ISREJECTED,STARTDATE,USERABSENCEID,USERHASSEEN,USERID,WIDTH) values ('1','ne',0,8,'2020-02-06',1,1,'2020-01-30',89,'1',348,160);
  </code></pre>
  <p>Can someone tell me, where I made mistake ? What is wrong here ?</p>