wolph

CREATE OR REPLACE FUNCTION escape_json (text) RETURNS text AS $$
SELECT replace($1, '''', '\'''); $$ LANGUAGE SQL IMMUTABLE;


CREATE OR REPLACE FUNCTION to_json(text) RETURNS text AS $$
SELECT escape_json($1) $$ LANGUAGE SQL IMMUTABLE;


CREATE OR REPLACE FUNCTION to_json(KEY text, value text) RETURNS text AS $$
SELECT '''' || to_json($1) || ''': ''' || to_json($2) || ''''; $$ LANGUAGE SQL IMMUTABLE;

ohneda

import static java.lang.Math.*
import static java.math.RoundingMode.CEILING

class StandardDeviationCategory {

    static Double mean(Collection list) {
        list.with{
            scale(sum() / size())
        }
    }

hgmnz

Types of index scans

Indexes

Sequential Scan:

• Read every row in the table
• No reading of index. Reading from indexes is also expensive.