layout: global title: Nan Semantics displayTitle: NaN Semantics license: | Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

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There is specially handling for not-a-number (NaN) when dealing with float or double types that does not exactly match standard floating point semantics. Specifically:

  • NaN = NaN returns true.
  • In aggregations, all NaN values are grouped together.
  • NaN is treated as a normal value in join keys.
  • NaN values go last when in ascending order, larger than any other numeric value.