Is it possible to add data in a query?

jfperea :

I want to bring a field from a table and add 1 to that field, is it possible?

I tried this way, but the only thing it does is put 1 always.

try {
    ps = cc.conectar.prepareStatement("UPDATE personeros SET votos = '" + 1 + 
                                      "' WHERE numero = '" + candidato + "'");
    ps.executeUpdate();
} catch (Exception e) {
    System.out.println("Error: " + e);
}

Tim Biegeleisen :

The syntax you want here is:

SET votos = votos + 1

Full code:

try {
    ps = cc.conectar.prepareStatement("UPDATE personeros SET votos = votos + 1 WHERE numero = ?");
    ps.setInt(1, candidato);
    ps.executeUpdate();
}
catch (Exception e) {
    System.out.println("Error: " + e);
}

As a side note, in my edit I am using a placeholder ? to which I am binding the value candidato. This is the whole point of using prepared statements, to avoid having to concatenate together literal fragments in your SQL string.

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