List of template classes

Quinlan Morake <>
Tue, 10 Sep 2013 12:40:12 -0700 (PDT)
Good day,

I have the following code and am uncertain as to how it should best done / =
thought of. I'm creating a "data access layer", and am aware that there are=
 c++ libraries for this, but am just doing it for the practice. I would lik=
e to have a dbField class, that holds the various column info, that is the =
name, type and data. A dbClass would then hold a list of dbFields, mapping =
to the columns available in the table. The dbField will thus have different=
 data depending on that of the database column, i.e. integer / varchar / bi=
t etc.

My implementation thinking is as follows

enum eDbFieldType
  Varchar, Integer, Boolean

template <class T>
class dbField
    // Name of column in the database
    QString fieldName;
    // Column datatype
    eDbFieldType dtColumn;
    // Data the field contains
    T data;

    void setData(T);
    T getData();

class DbClass
    map<QString, dbField<> > mDbFields;

After loading the data from the database into the dbField, I may have to do=
 other things to it depending on its type, for example to base64 decode/enc=
ode, etc when getData() is called, and then return the data.

I figure I could use a void* for data, is that what is generally done in th=
is type of situation? I've read that templates are preferable to void* but =
is that the case here and can they be used? Or should I be thinking differe=
ntly and do something different? I'm ideally trying to avoid casting.

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