Cod with Cucumber Sauce

Cut cucumber lengthwise in half; with tip of spoon, scrape out seeds. Coarsely chop unpeeled cucumber and place in medium bowl; toss with 1/2 teaspoon salt; set aside. Coarsely chop radishes; set aside. On waxed paper, combine flour, pepper, and 1/4 teaspoon salt. Dip each piece of cod fillet in flour mixture to coat. In nonstick 12-inch skillet over medium-high heat, in hot salad oil, cook cod 10 minutes, turning fish once, until fish flakes easily when tested with a fork. With hand, squeeze cucumber to remove excess liquid. Into bowl with cucumber, stir radishes, mayonnaise, and white wine vinegar. Place cod on 4 dinner plates; top with cucumber sauce.