23 lines
476 B
MySQL
23 lines
476 B
MySQL
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-- source: https://wiki.postgresql.org/wiki/Aggregate_Median
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CREATE OR REPLACE FUNCTION _final_median(NUMERIC [])
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RETURNS NUMERIC AS
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$$
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SELECT AVG(val)
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FROM (
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SELECT val
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FROM unnest($1) val
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ORDER BY 1
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LIMIT 2 - MOD(array_upper($1, 1), 2)
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OFFSET CEIL(array_upper($1, 1) / 2.0) - 1
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) sub;
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$$
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LANGUAGE 'sql' IMMUTABLE;
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CREATE AGGREGATE median( NUMERIC ) (
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SFUNC =array_append,
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STYPE = NUMERIC [],
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FINALFUNC =_final_median,
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INITCOND ='{}'
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);
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