title: "Illegal mix of collations for operation 'concat'" appears after data base import
body: <p>In my old site, this problem does not exist. But after I have changed the server and imported the data base, this message appears. The PHP version is 5.3 and this is the code:</p>
  
  <pre><code>$sql = "SELECT * FROM movcaixa 
  
      WHERE data BETWEEN '$data1' AND '$data2' AND empresa = $empresa 
  
      ORDER BY data ASC";
     $resMovCaixa = mysql_query($sql, $cnn) or die('Falha na conexão com o banco de dados');
     $sql = "SELECT cp.id AS codigo, CONCAT('Pagamento ref. a ', des.descricao, ', conforme doc. nº ',  cp.documento) AS hist, DATE_FORMAT(cp.quitacao, '%d/%m/%Y') AS data, cp.valorpago AS vlr, cp.documento AS doc, fr.nome AS forn, des.descricao AS desp 
  
      FROM contaspagar cp, fornecedor fr, despesa des 
  
      WHERE cp.fornecedor = fr.id AND cp.despesa = des.id AND cp.quitacao BETWEEN '$data1' AND '$data2' AND empresa = $empresa 
  
      ORDER BY data ASC";
      $resContasPagar = mysql_query($sql, $cnn) or die(mysql_error($cnn));
      $sql = "SELECT cr.id AS codigo, DATE_FORMAT(cr.quitacao, '%d/%m/%Y') AS data, CONCAT('Recebimento ref. ', cli.nome, ', conforme doc. ', cr.documento) AS hist, cr.valorpago AS vlr, cr.documento AS doc, cs.descricao AS cont 
  
      FROM contasreceber cr, contratoservico cs, cliente cli 
  
      WHERE cr.contratoservico = cs.id AND cs.cliente = cli.id AND cr.quitacao BETWEEN '$data1' AND '$data2' AND empresa = $empresa 
  
      ORDER BY cr.quitacao";
  </code></pre>
  
  <p>Can somebody help me?</p>