Running Dissolve on the output of a previous dissolve run will rarely reduce the number of features in the output when the original processing divided and processed the inputs using adaptive tiling. Tile boundaries are preserved in the output features to prevent the creation of features that are too large to be used by ArcGIS. Any record with a frequency value of 2 has been tiled. To determine the features that have been tiled, run the Frequency tool on the result of this tool, specifying the same fields used in the dissolve process for the Frequency Field(s) parameter. To prevent this, Dissolve may divide and process the input features using an adaptive tiling algorithm. This limitation could cause an error to occur, as the dissolve process may require more memory than is available. The availability of physical memory may limit the amount (and complexity) of input features that can be processed and dissolved into a single output feature. For more details, see Geoprocessing with large datasets. This tool will use a tiling process to handle very large datasets for better performance and scalability. The count returns the number of values included in the statistical calculation, which in this case is 2. For example, the average of 10, 5, and a null is 7.5 ((10 + 5) / 2). Null values are excluded from all statistical calculations. For extremely large features created by the Dissolve tool, the Dice tool may have to be used to split the large features to solve processing, display, or performance problems. To avoid these potential problems, use the Create multipart features parameter to create single part features to split potentially larger multipart features into many smaller features. Problems may also occur if the dissolve output created a feature at the maximum size on one machine, and this output was moved to a machine with less available memory. Very large features may cause processing or display problems and/or have poor performance when drawn on a map or when edited. This is especially true when there is a small number of unique values in the Dissolve Field(s) or when dissolving all features into a single feature. For example, if the SUM statistic is used on a field named POP, the output will have a field named SUM_POP.ĭissolve can create very large features in the output feature class. The statistic used to summarize attributes is added to the output feature class as a single field with the naming standard of statistic type + underscore + input field name. The attributes of the features that become aggregated by dissolve can be summarized or described using a variety of statistics. Learn more about how Dissolve works Illustration Usage Aggregates features based on specified attributes.