ALTER AGGREGATE changes the definition of an aggregate function. The only currently available functionality is to rename the aggregate function.
The name (optionally schema-qualified) of an existing aggregate function.
The argument data type of the aggregate function, or * if the function accepts any data type.
The new name of the aggregate function.
To rename the aggregate function myavg for type integer to my_average:
ALTER AGGREGATE myavg(integer) RENAME TO my_average;
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