Michael Giannakopoulos wrote: > I would like to ask if there is any way to make an aggregate function to take a set of tuples as an > input variable. I know that an actual aggregate function receives each tuple one at a time and process > it on the fly. However I want to store tuples in an incremental fashion so as to process them in a > batch approach in the finalaggr function. Think for example implementing logistic regression (which is > an OLAP query by its nature). I want to support it with the current features that PostgreSQL provides > from which the closest feature is an aggregate. However an aggregate function feeds me one a tuple for > each call, but I would like to have access to a batch of tuples per function call. Is there any > possible way to perform something like this? If you write in C, there is nothing that keeps you from storing all the rows that come in in memory allocated in a suitable MemoryContext and process them all at the end. You might run out of memory though. Yours, Laurenz Albe -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
