Syntax
GROUPCONCATDISTINCT(<any>[; <number>])
Description
Creates a list of all uniqueall unique non-null values seen in a group (currently, max. 1000 values are collected). The first argument is the column containing values that should be concatenated. The second value is an optional constant used to set a maximum number of values to avoid overflow problems with very large groups. The maximum number of values defaults to 1000. If more than the configured maximum number n of values are seen, the top n values in ascending order are kept.
The concatenated values are returned as a list.
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