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Ïðîãðàììèðîâàíèå >> Ïîíÿòèå sql
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(NULL)..........................................................................................112 ÈÑÏÎËÜÇÎÂÀÍÈÅ COUNT ÂÌÅÑÒÎ EXISTS........................................................................................................................113 ÐÅÇÞÌÅ......................................................................................................................................................................................114 ÐÀÁÎÒÀ Ñ SQL...........................................................................................................................................................................114 ÈÑÏÎËÜÇÎÂÀÍÈÅ ÏÐÅÄËÎÆÅÍÈß UNION.............................................................................115 ÎÁÚÅÄÈÍÅÍÈÅ ÌÍÎÃÎ×ÈÑËÅÍÍÛÕ ÇÀÏÐÎÑΠ ÎÄÈÍ...............................................................................................116 ÊÎÃÄÀ ÂÛ ÌÎÆÅÒÅ ÄÅËÀÒÜ ÎÁÚÅÄÈÍÅÍÈÅ ÌÅÆÄÓ 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SQL...........................................................................................................................................................................125 ÂÂÎÄ, ÓÄÀËÅÍÈÅ È ÈÇÌÅÍÅÍÈÅ ÇÍÀ×ÅÍÈÉ ÏÎËÅÉ...........................................................127 ÊÎÌÀÍÄÛ ÌÎÄÈÔÈÊÀÖÈÈ ßÇÛÊÀ DML...............................................................................................................................128 ÂÂÎÄ ÇÍÀ×ÅÍÈÉ.......................................................................................................................................................................128 ÂÑÒÀÂÊÀ ÏÓÑÒÛÕ ÓÊÀÇÀÒÅËÅÉ (NULL)...............................................................................................................................128 ÈÌÅÍÎÂÀÍÈÅ ÑÒÎËÁÖÀ ÄËß ÂÑÒÀÂÊÈ (INSERT).............................................................................................................129 ÂÑÒÀÂÊÀ 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