The Dow and the S&P 500 slipped on Friday as the U.S. dollar's advance led investors to pare back risky bets, but the Nasdaq edged higher as upbeat results from Oracle and Research In Motion boosted optimism about technology spending.

The U.S. dollar index <.DXY> climbed 0.5 percent, a move that put pressure on shares of natural resource companies and weighed on exporters like Caterpillar Inc , which shed nearly 2 percent.

Shares of consumer-oriented companies were among the casualties, with the S&P retail index down 1.2 percent.

Geopolitical concerns supported the flight to the U.S. dollar following reports that 11 Iranian troops had entered Iraqi territory and raised the Iranian flag at an oilfield whose ownership is disputed by Iran.

I think we're seeing a continued flight to safety, said Tom Schrader, managing director of U.S. equity trading at Stifel Nicolaus Capital Markets in Baltimore.

The stronger the dollar gets it means investors will be unwinding the dollar carry trade and that's going to put upward pressure on the dollar and downward pressure on the stocks.

The Dow Jones industrial average <.DJI> fell 33.63 points, or 0.33 percent, to 10,274.63. The Standard & Poor's 500 Index <.SPX> dropped 0.57 point, or 0.05 percent, to 1,095.51. The Nasdaq Composite Index <.IXIC> rose 13.04 points, or 0.60 percent, to 2,193.09.

The indexes had opened strongly but then lost ground late morning.

In tech news, Oracle Corp reported a bigger-than-expected increase in new software sales and BlackBerry maker Research In Motion Ltd gave a strong forecast.

Oracle shares rose 7 percent to $24.47, while RIM's Nasdaq-traded shares jumped 9 percent to $69.19.

(Editing by Kenneth Barry)