Quadruple witching refers to when market index futures, market index options, stock options, and stock futures all expire on the same day.

股指期货，股指期权，单只股票期权和期货全部同一天到期的日子。

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Index options like UNIQUE and CLUSTER, and access methods like B-Tree, R-Tree and user-defined access methods can apply to both functional and non-functional indexes.

诸如unique和CLUSTER等索引选项，以及B - Tree、r - Tree等访问方法和用户定义的访问方法，可以同时应用于函数索引和非函数索引。

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In 2001, Vanderbilt's Mr. Whaley developed an index to exploit the high price of index options.

WSJ: Upside: Options for Nervous Investors

We trade everything from equity and index options to longs and shorts on individual stocks.

FORBES: Wall Street Winners: Defying Gravity

Index options, traded at the Chicago Mercantile Exchange and the Chicago Board Options Exchange, work like options on individual stocks.

FORBES: When the Markets Sleep