{ "name": "probabilistic_estimator", "abstract": "Estimates number of distinct elements in a data set (aggregate and a data type).", "description": "Provides an alternative to COUNT(DISTINCT) aggregate, computing an estimate of number of distinct values, and a data type that may be used within a table (and updated continuously). This implementation is based on probabilistic counting (see the paper 'Probalistic Counting Algorithms for Data Base Applications' by Flajolet and Martin, published in 1985).", "version": "1.1.0", "maintainer": "Tomas Vondra ", "license": "bsd", "prereqs": { "runtime": { "requires": { "PostgreSQL": "9.0.0" } } }, "provides": { "probabilistic_estimator": { "file": "sql/probabilistic_counter--1.1.sql", "docfile" : "README.md", "version": "1.1.0" } }, "resources": { "repository": { "url": "https://tvondra@github.com/tvondra/distinct_estimators.git", "web": "http://github.com/tvondra/distinct_estimators", "type": "git" }, "x_blog": "http://www.fuzzy.cz/en/articles/aggregate-functions-for-distinct-estimation/" }, "tags" : ["distinct", "count", "aggregate", "estimate"], "meta-spec": { "version": "1.0.0", "url": "http://pgxn.org/meta/spec.txt" }, "release_status" : "testing" }