m_array.AddKey(PR_ID); //primary key
m_array.AddColumn(PR_CREATIONDATE, t_("Creation Date"), 10)
    .SetConvert(Single<ConvertYourIntBasedDate>());
...
m_array.AddColumn(COM_NAME, t_("Company Name"), 10);
...

SqlSet GetSqlColumns(const ArrayCtrl &a_array)
{
	SqlSet cols;
	for(int i = 0; i < a_array.GetIndexCount(); i++)
		if(!a_array.GetId(i).IsNull())
			cols.Cat(SqlId(a_array.GetId(i)));
	return cols;
}

SqlSet cols = GetSqlColumns(m_array);
Sql sql;
sql * ::Select(Distinct(cols))
	.From(PROJECT)
	.LeftJoin(COMPANY)
	.On(COM_ID == PR_COMPANYID)
	.Where(1)
	.OrderBy(PR_ID)
;

for(;;) {
	Vector<Value> row;
	if(!sql.Fetch(row)) break;
	m_array.Add(row);
}

struct ConvCompany : Convert
{
        Value Format(const Value &q) const
        {
			SQL * Select(COM_NAME).From(COMPANY).Where(COM_ID == q);
			String company;
			if(SQL.Fetch())
				company = SQL[COM_NAME];
			else
				company = "";
			return q.IsNull() ? Null : company;
        }
};

.....
.....

projects.AddColumn(VPR_COMPANYID, t_("Customer")).SetConvert(Single<ConvCompany>());

projects.SetTable(PROJECTV),Leftjoined(COMPANY,VPR_COMPANYID),AS_PREFIX(VCOM_);
projects.AddColumn(VCOM_COMPANYNAME, t_("Customer"));

struct NameConvert : Convert {
	VectorMap<int, String> name;
	VectorMap<int, String> surname;
	virtual Value Format(const Value& q) const;
	void LoadAttrs();
};

Value NameConvert::Format(const Value& q) const
{
	return surname.Get(q, String()) + ' ' + name.Get(q, String());
}

void NameConvert::LoadAttrs()
{
	name.Clear();
	surname.Clear();
	Sql sql;
	sql * Select(SUBJECT_ID, ATTR, TEXT).From(SUBJECT_ATTR)
	      .OrderBy(Descending(Nvl(TILL, Date::High())));
	while(sql.Fetch()) {
		int sid = sql[SUBJECT_ID];
		String id = sql[ATTR];
		if(id == "NAME" && name.Find(sid) < 0)
			name.Add(sid, sql[TEXT]);
		if(id == "LASTNAME" && surname.Find(sid) < 0)
			surname.Add(sid, sql[TEXT]);
	}
}

	MySqlSession session;
	if(!session.Connect(app.mysql_username, app.mysql_password, app.mysql_database, app.mysql_server)) {
		printf("Can't connect with MySql\n");
		PromptOK(t_("Can't connect with MySql"));
		return;
	}
	mysql_set_character_set(session, "utf8");
	
	SQL = session;
	Sql sql(session);

void Sum(int id) {
  return SQL % Select(SqlSum(MONEY)).From(TABLE).Where(ID == id);
}

void PrintSums() {
  SQL * Select(NAME, MONEY_ID).From(TABLE);
  while(SQL.Fetch())
     Print(SQL[NAME], Sum(SQL[MONEY_ID]);
}

Value ConvNomencl::Format(const Value& q) const
{
	static VectorMap<int, String> nom;
	static Time lastcleartime;
	if(GetSysTime()-lastcleartime > 60){
		nom.Clear();
		lastcleartime=GetSysTime();
	}
	if(nom.GetCount()==0) nom.Add(0, " "); // <==adding empty entry there. 
	int q1=q;
	int f = nom.Find(q1);
	if(f > 0){
		String s;
		s = nom.Get(q1);
		return s;
	} else {
		Sql sql;
		sql * SqlSelect(NOM_ID,NOM_NAME).From(NOMENCL).Where(NOM_ID == q);
		String nomencl;
		if(sql.Fetch()) {
			int sid = sql[NOM_ID];
			nom.Add(sid, sql[NOM_NAME]);
			nomencl = sql[NOM_NAME];
		} else {
			nomencl = "";
		}
		return nomencl;
	}
}

struct ConvCompany : Convert
{
	virtual Value Format(const Value& q) const;
};

struct ConvNomencl : Convert
{
	virtual Value Format(const Value& q) const;
};

struct ConvManager : Convert
{
	virtual Value Format(const Value& q) const;
};

Value ConvCompany::Format(const Value &q) const
{
	if(q.IsNull()) return Null;
	static VectorMap<int, String> comp;
	static Time lastcleartime;
	if(GetSysTime()-lastcleartime > 600){
		comp.Clear();
		lastcleartime=GetSysTime();
	}
	int f = comp.Find(int(q));
	if(f >= 0){
		return comp[f];
	} else {
		Sql sql;
		sql * Select(COM_NAME).From(COMPANY).Where(COM_ID == q);
		String company;
		if(sql.Fetch()) {
			int sid = int(q);
			company = sql[COM_NAME];
			comp.Add(sid, company);
		} else {
			company = "";
		}
		return company;
	}
}
Value ConvNomencl::Format(const Value& q) const
{
	if(q.IsNull()) return Null;
	static VectorMap<int, String> nom;
	static Time lastcleartime;
	if(GetSysTime()-lastcleartime > 600){
		nom.Clear();
		lastcleartime=GetSysTime();
	}
	int f = nom.Find(int(q));
	if(f >= 0){
		return nom[f];
	} else {
		Sql sql;
		sql * SqlSelect(NOM_ID,NOM_NAME).From(NOMENCL).Where(NOM_ID == q);
		String nomencl;
		if(sql.Fetch()) {
			int sid = sql[NOM_ID];
			nomencl = sql[NOM_NAME];
			nom.Add(sid, nomencl);
		} else {
			nomencl = "";
		}
		return nomencl;
	}
}

Value ConvManager::Format(const Value &q) const
{
	if(q.IsNull()) return Null;
	static VectorMap<int, String> man;
	static Time lastcleartime;
	if(GetSysTime()-lastcleartime > 600){
		man.Clear();
		lastcleartime=GetSysTime();
	}
	int f = man.Find(int(q));
	if(f >= 0){
		return man[f];
	} else {
		Sql sql;
		sql * SqlSelect(USR_REALNAME).From(USER).Where(USR_ID == q);
		String manager;
		if(sql.Fetch()) {
			int sid = int(q);
			manager = sql[USR_REALNAME];
			man.Add(sid, manager);
		} else {
			manager = "";
		}
		return manager;
	}
}

template <SqlId TBL ,SqlId ID, SqlId NAME,int CLEARTIME>
struct ConvDict : Convert
//ConvDict<COMPANY,COM_ID,COM_NAME,600>()
{
	virtual Value Format(const Value& q) const {
		if(q.IsNull()) return Null;
		static VectorMap<int, String> dict;
		static Time lastcleartime;
		if(GetSysTime()-lastcleartime > CLEARTIME){
			dict.Clear();
			lastcleartime=GetSysTime();
		}
		int f = dict.Find(int(q));
		if(f >= 0){
			return dict[f];
		} else {
			Sql sql;
			sql * Select(NAME).From(TBL).Where(ID == q);
			String s;
			if(sql.Fetch()) {
				int sid = int(q);
				s = sql[NAME];
				dict.Add(sid, s);
			} else {
				s = "";
			}
			return s;
		}
	}
};

struct ConvDict : Convert
{
    SqlId TBL ,ID, NAME, CLEARTIME;
public:
    void setValues(SqlId _TBL ,SqlId _ID, SqlId _NAME,int _CLEARTIME)
    {
        TBL = _TBL;
        ID = _ID;
        NAME = _NAME;
        CLEARTIME = _CLEARTIME;
    }
// ...

(Single<ConvLookup<COMPANY,COM_ID,COM_NAME> >() )

template<typename T> T& LookupSetup ( T& grid, SqlId& tablename, SqlId& colid, SqlId& colname, bool showid = false, bool valueiscode = true, SqlBool where = true );
template<>		DropGrid& LookupSetup ( DropGrid& grid, SqlId& tablename, SqlId& colid, SqlId& colname, bool showid, bool valueiscode, SqlBool where );
template<>		WithDropChoice<EditString>& LookupSetup ( WithDropChoice<EditString>& grid, SqlId& tablename, SqlId& colid, SqlId& colname, bool showid, bool valueiscode, SqlBool where );
template<>		DropList& LookupSetup ( DropList& grid, SqlId& tablename, SqlId& colid, SqlId& colname, bool showid, bool valueiscode, SqlBool where );

template<typename T> T& LookupSetup1 ( T& grid, SqlId& tablename, SqlId& colid, SqlId& colname1, SqlId& colname2, bool showid = false, bool valueiscode = true, SqlBool where = true );
template<>		DropGrid& LookupSetup1 ( DropGrid& grid, SqlId& tablename, SqlId& colid, SqlId& colname1, SqlId& colname2, bool showid, bool valueiscode, SqlBool where );
template<>		WithDropChoice<EditString>& LookupSetup1 ( WithDropChoice<EditString>& grid, SqlId& tablename, SqlId& colid, SqlId& colname1, SqlId& colname2, bool showid, bool valueiscode, SqlBool where );


template< SqlId &LookupTable, SqlId &LookupCode, SqlId &LookupValue, bool show_id=false >
struct ConvLookup : Convert
{
     Value Format ( const Value &q ) const
     {
          int sid = q;
          if ( q.IsNull() ){
               return Null;
          } else if ( q == 0 ) {
               return "";
          }
          
          static VectorMap<int, Value> valuecache;
          static Time lastcleartime;
          if ( GetSysTime() - lastcleartime > 600 )
          {
               valuecache.Clear();
               lastcleartime = GetSysTime();
          }
          if ( valuecache.Get ( sid, "X") != "X" )
          {
               if (show_id) {
                    return AsString ( sid ) + ": " + AsString(valuecache.Get ( sid, Value() ));
               } else {
                    return valuecache.Get ( sid, Value() );
               }
          }
          else
          {
               Sql sql;
               sql * Select ( LookupValue ).From ( LookupTable ).Where ( LookupCode == sid );
               if ( sql.Fetch() )
               {
                    valuecache.Add ( sid, AsString(sql[LookupValue]) );
                    if ( valuecache.Get ( sid, "X" ) != "X" )
                    {
                         if (show_id) {
                              return AsString ( sid ) + ": " + AsString(valuecache.Get ( sid, Value() ) );
                         } else {
                              return valuecache.Get ( sid, Value() );
                         }
                    }
                    return sql[LookupValue] ;
               }
               else
               {
                    return  AsString ( sid ) + ": ??? " + t_(~LookupTable) + " ???" ;
               }
          }
          return  "ERROR RETURN PLACE" ;
     }
};

template<typename T> T& LookupSetup ( T& grid, SqlId& tablename, SqlId& colid, SqlId& colname, bool showid, bool valueiscode, SqlBool where ) {}

template<> DropGrid& LookupSetup ( DropGrid& grid, SqlId& tablename, SqlId& colid, SqlId& colname, bool showid, bool valueiscode, SqlBool where )
{
     Sql sql;

     if ( grid.GetList().GetColumnCount() == 0 )
     {
          grid.ClearButton();
          grid.Resizeable ( false );
          grid.AddColumn ( colid, "", showid ? 10 : 0, true );
          grid.AddColumn ( colname,  showid  ? " : " : "", 70 );

          if ( showid )
               grid.SetValueColumn ( 0 );
          else
               grid.SetValueColumn ( 1 );

          if ( valueiscode )
          {
               grid.SetKeyColumn ( 0 );
          }
          else
          {
               grid.SetKeyColumn ( 1 );
          }

          if ( showid )
          {
               grid.AddValueColumn ( 0 );
          }
          grid.AddValueColumn ( 1 );
          
          grid.SetFindColumn ( 1 );

          grid.NoHeader();

          grid.ColorRows();
     }

     grid.Clear();

     sql * Select ( colid,
                    colname ).From ( tablename ).Where ( where ).OrderBy ( colid );

     while ( sql.Fetch() )
     {
          grid.Add ( sql[colid], sql[colname] );
     }

     return grid;
}

template<> WithDropChoice<EditString>& LookupSetup ( WithDropChoice<EditString>& grid, SqlId& tablename, SqlId& colid, SqlId& colname, bool showid, bool valueiscode, SqlBool where )
{
     Sql sql;
     grid.ClearList();
     sql * Select ( colname ).From ( tablename ).Where ( where ).OrderBy ( colname );

     while ( sql.Fetch() )
     {
          grid.AddList ( sql[colname] );
     }

     return grid;
}

template<> DropList& LookupSetup ( DropList& grid, SqlId& tablename, SqlId& colid, SqlId& colname, bool showid, bool valueiscode, SqlBool where )
{
     Sql sql;

     if ( grid.GetList().GetColumnCount() == 0 )
     {
          grid.SetDropLines ( 12 );
     }

     grid.ClearList();

     sql * Select ( colname ).From ( tablename ).Where ( where ).OrderBy ( colname );

     while ( sql.Fetch() )
     {
          grid.Add ( sql[colname] );
     }

     return grid;
}


template<typename T> T& LookupSetup1 ( T& grid, SqlId& tablename, SqlId& colid, SqlId& colname1, SqlId& colname2, bool showid, bool valueiscode, SqlBool where ) {}

template<> DropGrid& LookupSetup1 ( DropGrid& grid, SqlId& tablename, SqlId& colid, SqlId& colname1, SqlId& colname2, bool showid, bool valueiscode, SqlBool where )
{
     Sql sql;

     if ( grid.GetList().GetColumnCount() == 0 )
     {
          grid.ClearButton();
          grid.Resizeable ( false );
          grid.AddColumn ( colid, "", showid ? 10 : 0, true );
          grid.AddColumn ( colname1, valueiscode ? " : " : "", 70 );
          grid.AddColumn ( colname2, "", 70 );
          if ( showid )
               grid.SetValueColumn ( 0 );
          else
               grid.SetValueColumn ( 1 );

          if ( valueiscode )
          {
               grid.SetKeyColumn ( 0 );
          }
          else
          {
               grid.SetKeyColumn ( 1 );
          }

          if ( showid )
          {
               grid.AddValueColumn ( 0 );
          }
          grid.AddValueColumn ( 1 );
          
          grid.SetFindColumn ( 1 );

          grid.NoHeader();

          grid.ColorRows();
     }

     grid.Clear();

     sql * Select ( colid,
                    colname1, colname2 ).From ( tablename ).Where ( where ).OrderBy ( colid );

     while ( sql.Fetch() )
     {
          grid.Add ( sql[colid], sql[colname1], sql[colname2] );
     }

     return grid;
}

template<> WithDropChoice<EditString>& LookupSetup1 ( WithDropChoice<EditString>& grid, SqlId& tablename, SqlId& colid, SqlId& colname1, SqlId& colname2, bool showid, bool valueiscode, SqlBool where )
{
     Sql sql;
     grid.ClearList();
     sql * Select ( colname1, colname2 ).From ( tablename ).Where ( where ).OrderBy ( colname1 );

     while ( sql.Fetch() )
     {
          grid.AddList ( AsString ( sql[colname1] ) + " " + AsString ( sql[colname2] ) );
     }

     return grid;
}

listvisitor.AddColumn ( VISR_COMPANY_ID, t_("Company"), 265 ).SetConvert(Single<ConvLookup<COMPANY,COM_ID,COM_NAME> >()).HeaderAlignCenter();