Çäðàâñòâóéòå, èìååòñÿ òàáëèöà. Â íåé óêàçàíû íîìåðà, ñ êîòîðûõ îñóùåñòâëÿëñÿ âûçîâ, äàòà è äëèòåëüíîñòü âûçîâà. Íåîáõîäèìî ñãðóïïèðîâàòü äàííûå, ÷òîáû ñîáèðàëàñü ñòàòèñòèêà çà êàæäûé äåíü. Íàïðèìåð,
Èñõîäíûé âàðèàíò: Òåëåôîí Äàòà .........Äëèòåëüíîñòü
...................................123...01.01.16 16:21......38
...................................123...01.01.16 17:15......15
...................................123...02.01.16 11:11......27
...................................124...01.01.16 10:20......2
...................................124...30.01.16 19:15......0
...................................124...30.01.16 20:15......7
Íóæíî:
....................................123...01.01.16......53
....................................123...02.01.16......27
....................................124...01.01.16......2
....................................124...30.01.16......7
Ò.å íóæíî, ÷òîáû îí ñóììèðîâàë äëèòåëüíîñòè âûçîâîâ ñ êàæäîãî íîìåðà çà äåíü è âûäàâàë ñòàòèñòèêó, åùå íå ïëîõî áûëî áû óêàçàòü êîë-âî çâîíêîâ â äåíü ñ êàæäîãî íîìåðà, íî ýòî ïîòîì.
Ïðîáîâàë âîò òàê:
SELECT NUMTEL, DATEPART("d", DATECALL), TIMECALL
FROM Ëèñò1
GROUP BY NUMTEL, DATEPART("d", DATECALL);
Íî ðåçóëüòàò íå òîò
http://www.sql.ru/forum/1222585/preobrazovanie-dat-v-sql