title: PIG - matching toDate function
body: <p>I am trying to cast a string into a datetime object in hadoop pig. But Grunt give me a strange error message : it is like It can't choose the correct 'ToDate' function. It is asking for an 'explicit cast', but I have no clue how to do so. Any idea ? </p>
  
  <p>=> ERROR 1045:  Could not infer the matching function for org.apache.pig.builtin.ToDate as multiple or none of them fit. Please use an explicit cast.</p>
  
  <pre><code>grunt&gt; describe infos_by_nu_affa;
  infos_by_nu_affa: {NU_AFFA: bytearray,affaires: {(NU_AFFA:bytearray,NU_PCP: bytearray,debut: bytearray,fin: bytearray)},prestations: {(NU_AFFA: bytearray,montant: bytearray,date: bytearray,NU_presta: bytearray,beneficiaire: bytearray)},clients: {(NU_PCP: bytearray,nom: bytearray,prenom: bytearray)}}
  
  
  derivees = foreach infos_by_nu_affa  generate *, ToDate(affaires.debut, 'dd/MM/yyyy') as (debut:datetime);
  2015-03-28 15:46:36,089 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1045: &lt;line 155, column 0&gt; Could not infer the matching function for org.apache.pig.builtin.ToDate as multiple or none of them fit. Please use an explicit cast.
  
  
  grunt&gt; dump infos_by_nu_affa
  (affaire5,{(affaire5,client5,01/01/14,05/01/15)},{},{(client5,enders,kililan)})
  (affaire6,{(affaire6,client6,01/01/13,01/06/14)},{},{(client6,blanco,martine)})
  (affaire7,{(affaire7,client7,01/01/10,02/03/13)},{},{(client7,sarah,moore)})
  (affaire8,{(affaire8,client8,01/01/15,01/01/01)},{},{(client8,evrard,dominique)})
  
  
  
  grunt&gt; derivees = foreach infos_by_nu_affa 
  &gt;&gt; generate *,
  &gt;&gt; COUNT(prestations) as nb_prestations,
  &gt;&gt; ToDate(affaires.debut, 'dd/MM/yy') as debut;
  2015-03-28 15:56:06,729 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1045: 
  &lt;line 155, column 0&gt; Could not infer the matching function for org.apache.pig.builtin.ToDate as multiple or none of them fit. Please use an explicit cast.
  </code></pre>