title: Subtracting a date from SYSDATE in ORACLE
body: <p>Subtracting a date from <code>SYSDATE</code> gives negative results:</p>
  
  <pre><code>select floor(SYSDATE - dateemb) from pilote;
  
  FLOOR(SYSDATE-DATEEMB)
  ----------------------
                  -29126
                  -29137
                  -29522
  </code></pre>
  
  <p>any solution to this?</p>
  
  <p>table pilote:</p>
  
  <pre><code>Name                                      Null?    Type
   ----------------------------------------- -------- ----------------------------
  
   NUMPIL                                    NOT NULL NUMBER
   NOMPIL                                             VARCHAR2(25)
   ADRPIL                                             VARCHAR2(25)
   SALAIRE                                            NUMBER
   COMMISSION                                         NUMBER
   DATEEMB                                            DATE
  </code></pre>
  
  <p>data used:</p>
  
  <pre><code>NUMPIL   NOMPIL    ADRPIL   SALAIRE   COMMISSION     DATEEMB
  ------- --------  -------- --------   ----------    ---------
  1333    FEDOI      NANTES   24000      0            01-MAR-92                           
  
  6589    DUVAL      PARIS    18600     5580          12-MAR-92
  
  7100    MARTIN     LYON     15600     16000         01-APR-93
  </code></pre>