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368df30427
This completes my project of improving usage of hashing for duplicate elimination (aggregate functions with DISTINCT remain undone, but that's for some other day). As with the previous patches, this means we can INTERSECT/EXCEPT on datatypes that can hash but not sort, and it means that INTERSECT/EXCEPT without ORDER BY are no longer certain to produce sorted output.
157 lines
3.6 KiB
SQL
157 lines
3.6 KiB
SQL
--
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-- UNION (also INTERSECT, EXCEPT)
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--
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-- Simple UNION constructs
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SELECT 1 AS two UNION SELECT 2;
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SELECT 1 AS one UNION SELECT 1;
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SELECT 1 AS two UNION ALL SELECT 2;
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SELECT 1 AS two UNION ALL SELECT 1;
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SELECT 1 AS three UNION SELECT 2 UNION SELECT 3;
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SELECT 1 AS two UNION SELECT 2 UNION SELECT 2;
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SELECT 1 AS three UNION SELECT 2 UNION ALL SELECT 2;
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SELECT 1.1 AS two UNION SELECT 2.2;
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-- Mixed types
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SELECT 1.1 AS two UNION SELECT 2;
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SELECT 1 AS two UNION SELECT 2.2;
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SELECT 1 AS one UNION SELECT 1.0::float8;
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SELECT 1.1 AS two UNION ALL SELECT 2;
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SELECT 1.0::float8 AS two UNION ALL SELECT 1;
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SELECT 1.1 AS three UNION SELECT 2 UNION SELECT 3;
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SELECT 1.1::float8 AS two UNION SELECT 2 UNION SELECT 2.0::float8 ORDER BY 1;
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SELECT 1.1 AS three UNION SELECT 2 UNION ALL SELECT 2;
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SELECT 1.1 AS two UNION (SELECT 2 UNION ALL SELECT 2);
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--
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-- Try testing from tables...
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--
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SELECT f1 AS five FROM FLOAT8_TBL
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UNION
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SELECT f1 FROM FLOAT8_TBL
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ORDER BY 1;
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SELECT f1 AS ten FROM FLOAT8_TBL
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UNION ALL
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SELECT f1 FROM FLOAT8_TBL;
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SELECT f1 AS nine FROM FLOAT8_TBL
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UNION
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SELECT f1 FROM INT4_TBL
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ORDER BY 1;
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SELECT f1 AS ten FROM FLOAT8_TBL
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UNION ALL
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SELECT f1 FROM INT4_TBL;
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SELECT f1 AS five FROM FLOAT8_TBL
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WHERE f1 BETWEEN -1e6 AND 1e6
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UNION
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SELECT f1 FROM INT4_TBL
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WHERE f1 BETWEEN 0 AND 1000000;
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SELECT CAST(f1 AS char(4)) AS three FROM VARCHAR_TBL
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UNION
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SELECT f1 FROM CHAR_TBL
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ORDER BY 1;
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SELECT f1 AS three FROM VARCHAR_TBL
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UNION
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SELECT CAST(f1 AS varchar) FROM CHAR_TBL
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ORDER BY 1;
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SELECT f1 AS eight FROM VARCHAR_TBL
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UNION ALL
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SELECT f1 FROM CHAR_TBL;
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SELECT f1 AS five FROM TEXT_TBL
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UNION
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SELECT f1 FROM VARCHAR_TBL
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UNION
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SELECT TRIM(TRAILING FROM f1) FROM CHAR_TBL
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ORDER BY 1;
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--
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-- INTERSECT and EXCEPT
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--
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SELECT q2 FROM int8_tbl INTERSECT SELECT q1 FROM int8_tbl;
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SELECT q2 FROM int8_tbl INTERSECT ALL SELECT q1 FROM int8_tbl;
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SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1;
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SELECT q2 FROM int8_tbl EXCEPT ALL SELECT q1 FROM int8_tbl ORDER BY 1;
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SELECT q2 FROM int8_tbl EXCEPT ALL SELECT DISTINCT q1 FROM int8_tbl ORDER BY 1;
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SELECT q1 FROM int8_tbl EXCEPT SELECT q2 FROM int8_tbl;
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SELECT q1 FROM int8_tbl EXCEPT ALL SELECT q2 FROM int8_tbl;
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SELECT q1 FROM int8_tbl EXCEPT ALL SELECT DISTINCT q2 FROM int8_tbl;
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--
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-- Mixed types
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--
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SELECT f1 FROM float8_tbl INTERSECT SELECT f1 FROM int4_tbl;
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SELECT f1 FROM float8_tbl EXCEPT SELECT f1 FROM int4_tbl ORDER BY 1;
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--
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-- Operator precedence and (((((extra))))) parentheses
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--
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SELECT q1 FROM int8_tbl INTERSECT SELECT q2 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl;
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SELECT q1 FROM int8_tbl INTERSECT (((SELECT q2 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl)));
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(((SELECT q1 FROM int8_tbl INTERSECT SELECT q2 FROM int8_tbl))) UNION ALL SELECT q2 FROM int8_tbl;
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SELECT q1 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1;
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SELECT q1 FROM int8_tbl UNION ALL (((SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1)));
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(((SELECT q1 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl))) EXCEPT SELECT q1 FROM int8_tbl ORDER BY 1;
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--
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-- Subqueries with ORDER BY & LIMIT clauses
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--
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-- In this syntax, ORDER BY/LIMIT apply to the result of the EXCEPT
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SELECT q1,q2 FROM int8_tbl EXCEPT SELECT q2,q1 FROM int8_tbl
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ORDER BY q2,q1;
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-- This should fail, because q2 isn't a name of an EXCEPT output column
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SELECT q1 FROM int8_tbl EXCEPT SELECT q2 FROM int8_tbl ORDER BY q2 LIMIT 1;
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-- But this should work:
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SELECT q1 FROM int8_tbl EXCEPT (((SELECT q2 FROM int8_tbl ORDER BY q2 LIMIT 1)));
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--
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-- New syntaxes (7.1) permit new tests
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--
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(((((select * from int8_tbl)))));
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