2018-06-21 00:30:03 +08:00
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-- Taken from https://wiki.postgresql.org/wiki/Count_estimate
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CREATE FUNCTION count_estimate(query text) RETURNS INTEGER AS
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$func$
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DECLARE
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rec record;
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ROWS INTEGER;
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BEGIN
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FOR rec IN EXECUTE 'EXPLAIN ' || query LOOP
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ROWS := SUBSTRING(rec."QUERY PLAN" FROM ' rows=([[:digit:]]+)');
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EXIT WHEN ROWS IS NOT NULL;
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END LOOP;
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RETURN ROWS;
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END
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2018-07-17 01:55:04 +08:00
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$func$ LANGUAGE plpgsql;
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-- Taken from https://stackoverflow.com/a/48013356/351721
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CREATE OR REPLACE FUNCTION jsonb_array_casttext(jsonb) RETURNS text[] AS $f$
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SELECT array_agg(x) || ARRAY[]::text[] FROM jsonb_array_elements_text($1) t(x);
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$f$ LANGUAGE sql IMMUTABLE;
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