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be3b265c94
as methods for implementing the DISTINCT step. This eliminates the former performance gap between DISTINCT and GROUP BY, and also makes it possible to do SELECT DISTINCT on datatypes that only support hashing not sorting. SELECT DISTINCT ON is still always implemented by sorting; it would take executor changes to support hashing that, and it's not clear it's worth the trouble. This is a release-note-worthy incompatibility from previous PG versions, since SELECT DISTINCT can no longer be counted on to deliver sorted output without explicitly saying ORDER BY. (Anyone who can't cope with that can consider turning off enable_hashagg.) Several regression test queries needed to have ORDER BY added to preserve stable output order. I fixed the ones that manifested here, but there might be some other cases that show up on other platforms.
100 lines
2.1 KiB
SQL
100 lines
2.1 KiB
SQL
--
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-- NUMEROLOGY
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-- Test various combinations of numeric types and functions.
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--
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--
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-- Test implicit type conversions
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-- This fails for Postgres v6.1 (and earlier?)
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-- so let's try explicit conversions for now - tgl 97/05/07
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--
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CREATE TABLE TEMP_FLOAT (f1 FLOAT8);
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INSERT INTO TEMP_FLOAT (f1)
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SELECT float8(f1) FROM INT4_TBL;
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INSERT INTO TEMP_FLOAT (f1)
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SELECT float8(f1) FROM INT2_TBL;
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SELECT '' AS ten, f1 FROM TEMP_FLOAT
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ORDER BY f1;
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-- int4
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CREATE TABLE TEMP_INT4 (f1 INT4);
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INSERT INTO TEMP_INT4 (f1)
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SELECT int4(f1) FROM FLOAT8_TBL
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WHERE (f1 > -2147483647) AND (f1 < 2147483647);
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INSERT INTO TEMP_INT4 (f1)
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SELECT int4(f1) FROM INT2_TBL;
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SELECT '' AS nine, f1 FROM TEMP_INT4
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ORDER BY f1;
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-- int2
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CREATE TABLE TEMP_INT2 (f1 INT2);
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INSERT INTO TEMP_INT2 (f1)
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SELECT int2(f1) FROM FLOAT8_TBL
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WHERE (f1 >= -32767) AND (f1 <= 32767);
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INSERT INTO TEMP_INT2 (f1)
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SELECT int2(f1) FROM INT4_TBL
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WHERE (f1 >= -32767) AND (f1 <= 32767);
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SELECT '' AS five, f1 FROM TEMP_INT2
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ORDER BY f1;
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--
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-- Group-by combinations
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--
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CREATE TABLE TEMP_GROUP (f1 INT4, f2 INT4, f3 FLOAT8);
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INSERT INTO TEMP_GROUP
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SELECT 1, (- i.f1), (- f.f1)
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FROM INT4_TBL i, FLOAT8_TBL f;
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INSERT INTO TEMP_GROUP
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SELECT 2, i.f1, f.f1
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FROM INT4_TBL i, FLOAT8_TBL f;
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SELECT DISTINCT f1 AS two FROM TEMP_GROUP ORDER BY 1;
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SELECT f1 AS two, max(f3) AS max_float, min(f3) as min_float
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FROM TEMP_GROUP
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GROUP BY f1
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ORDER BY two, max_float, min_float;
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-- GROUP BY a result column name is not legal per SQL92, but we accept it
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-- anyway (if the name is not the name of any column exposed by FROM).
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SELECT f1 AS two, max(f3) AS max_float, min(f3) AS min_float
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FROM TEMP_GROUP
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GROUP BY two
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ORDER BY two, max_float, min_float;
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SELECT f1 AS two, (max(f3) + 1) AS max_plus_1, (min(f3) - 1) AS min_minus_1
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FROM TEMP_GROUP
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GROUP BY f1
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ORDER BY two, min_minus_1;
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SELECT f1 AS two,
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max(f2) + min(f2) AS max_plus_min,
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min(f3) - 1 AS min_minus_1
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FROM TEMP_GROUP
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GROUP BY f1
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ORDER BY two, min_minus_1;
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DROP TABLE TEMP_INT2;
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DROP TABLE TEMP_INT4;
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DROP TABLE TEMP_FLOAT;
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DROP TABLE TEMP_GROUP;
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