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bec98a31c5
There's now only one transition value and transition function. NULL handling in aggregates is a lot cleaner. Also, use Numeric accumulators instead of integer accumulators for sum/avg on integer datatypes --- this avoids overflow at the cost of being a little slower. Implement VARIANCE() and STDDEV() aggregates in the standard backend. Also, enable new LIKE selectivity estimators by default. Unrelated change, but as long as I had to force initdb anyway...
50 lines
1.0 KiB
SQL
50 lines
1.0 KiB
SQL
--
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-- AGGREGATES
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--
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SELECT avg(four) AS avg_1 FROM onek;
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SELECT avg(a) AS avg_32 FROM aggtest WHERE a < 100;
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-- In 7.1, avg(float4) is computed using float8 arithmetic.
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-- Round the result to 3 digits to avoid platform-specific results.
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SELECT avg(b)::numeric(10,3) AS avg_107_943 FROM aggtest;
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SELECT avg(gpa) AS avg_3_4 FROM ONLY student;
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SELECT sum(four) AS sum_1500 FROM onek;
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SELECT sum(a) AS sum_198 FROM aggtest;
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SELECT sum(b) AS avg_431_773 FROM aggtest;
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SELECT sum(gpa) AS avg_6_8 FROM ONLY student;
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SELECT max(four) AS max_3 FROM onek;
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SELECT max(a) AS max_100 FROM aggtest;
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SELECT max(aggtest.b) AS max_324_78 FROM aggtest;
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SELECT max(student.gpa) AS max_3_7 FROM student;
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SELECT count(four) AS cnt_1000 FROM onek;
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SELECT count(DISTINCT four) AS cnt_4 FROM onek;
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select ten, count(*), sum(four) from onek group by ten;
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select ten, count(four), sum(DISTINCT four) from onek group by ten;
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SELECT newavg(four) AS avg_1 FROM onek;
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SELECT newsum(four) AS sum_1500 FROM onek;
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SELECT newcnt(four) AS cnt_1000 FROM onek;
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