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b26dfb9522
to be flexible about assignment casts without introducing ambiguity in operator/function resolution. Introduce a well-defined promotion hierarchy for numeric datatypes (int2->int4->int8->numeric->float4->float8). Change make_const to initially label numeric literals as int4, int8, or numeric (never float8 anymore). Explicitly mark Func and RelabelType nodes to indicate whether they came from a function call, explicit cast, or implicit cast; use this to do reverse-listing more accurately and without so many heuristics. Explicit casts to char, varchar, bit, varbit will truncate or pad without raising an error (the pre-7.2 behavior), while assigning to a column without any explicit cast will still raise an error for wrong-length data like 7.3. This more nearly follows the SQL spec than 7.2 behavior (we should be reporting a 'completion condition' in the explicit-cast cases, but we have no mechanism for that, so just do silent truncation). Fix some problems with enforcement of typmod for array elements; it didn't work at all in 'UPDATE ... SET array[n] = foo', for example. Provide a generalized array_length_coerce() function to replace the specialized per-array-type functions that used to be needed (and were missing for NUMERIC as well as all the datetime types). Add missing conversions int8<->float4, text<->numeric, oid<->int8. initdb forced.
431 lines
7.5 KiB
Plaintext
431 lines
7.5 KiB
Plaintext
--
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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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two
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-----
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1
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2
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(2 rows)
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SELECT 1 AS one UNION SELECT 1;
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one
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-----
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1
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(1 row)
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SELECT 1 AS two UNION ALL SELECT 2;
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two
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-----
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1
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2
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(2 rows)
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SELECT 1 AS two UNION ALL SELECT 1;
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two
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-----
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1
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1
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(2 rows)
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SELECT 1 AS three UNION SELECT 2 UNION SELECT 3;
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three
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-------
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1
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2
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3
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(3 rows)
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SELECT 1 AS two UNION SELECT 2 UNION SELECT 2;
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two
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-----
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1
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2
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(2 rows)
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SELECT 1 AS three UNION SELECT 2 UNION ALL SELECT 2;
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three
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-------
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1
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2
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2
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(3 rows)
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SELECT 1.1 AS two UNION SELECT 2.2;
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two
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-----
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1.1
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2.2
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(2 rows)
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-- Mixed types
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SELECT 1.1 AS two UNION SELECT 2;
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two
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-----
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1.1
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2
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(2 rows)
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SELECT 1 AS two UNION SELECT 2.2;
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two
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-----
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1
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2.2
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(2 rows)
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SELECT 1 AS one UNION SELECT 1.0;
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one
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-----
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1
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(1 row)
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SELECT 1.1 AS two UNION ALL SELECT 2;
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two
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-----
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1.1
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2
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(2 rows)
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SELECT 1.0 AS two UNION ALL SELECT 1;
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two
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-----
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1.0
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1
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(2 rows)
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SELECT 1.1 AS three UNION SELECT 2 UNION SELECT 3;
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three
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-------
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1.1
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2
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3
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(3 rows)
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SELECT 1.1 AS two UNION SELECT 2 UNION SELECT 2.0;
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two
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-----
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1.1
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2
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(2 rows)
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SELECT 1.1 AS three UNION SELECT 2 UNION ALL SELECT 2;
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three
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-------
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1.1
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2
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2
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(3 rows)
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SELECT 1.1 AS two UNION (SELECT 2 UNION ALL SELECT 2);
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two
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-----
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1.1
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2
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(2 rows)
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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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five
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-----------------------
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-1.2345678901234e+200
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-1004.3
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-34.84
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-1.2345678901234e-200
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0
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(5 rows)
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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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ten
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-----------------------
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0
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-34.84
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-1004.3
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-1.2345678901234e+200
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-1.2345678901234e-200
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0
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-34.84
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-1004.3
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-1.2345678901234e+200
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-1.2345678901234e-200
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(10 rows)
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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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nine
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-----------------------
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-1.2345678901234e+200
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-2147483647
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-123456
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-1004.3
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-34.84
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-1.2345678901234e-200
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0
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123456
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2147483647
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(9 rows)
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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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ten
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-----------------------
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0
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-34.84
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-1004.3
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-1.2345678901234e+200
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-1.2345678901234e-200
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0
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123456
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-123456
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2147483647
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-2147483647
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(10 rows)
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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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five
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-----------------------
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-1004.3
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-34.84
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-1.2345678901234e-200
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0
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123456
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(5 rows)
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SELECT f1 AS five FROM VARCHAR_TBL
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UNION
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SELECT f1 FROM CHAR_TBL;
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five
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------
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a
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a
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ab
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ab
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abcd
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(5 rows)
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SELECT f1 AS three FROM VARCHAR_TBL
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UNION
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SELECT TRIM(TRAILING FROM f1) FROM CHAR_TBL;
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three
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-------
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a
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ab
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abcd
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(3 rows)
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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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eight
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-------
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a
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ab
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abcd
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abcd
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a
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ab
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abcd
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abcd
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(8 rows)
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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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five
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-------------------
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a
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ab
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abcd
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doh!
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hi de ho neighbor
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(5 rows)
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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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q2
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------------------
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123
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4567890123456789
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(2 rows)
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SELECT q2 FROM int8_tbl INTERSECT ALL SELECT q1 FROM int8_tbl;
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q2
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------------------
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123
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4567890123456789
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4567890123456789
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(3 rows)
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SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl;
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q2
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-------------------
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-4567890123456789
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456
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(2 rows)
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SELECT q2 FROM int8_tbl EXCEPT ALL SELECT q1 FROM int8_tbl;
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q2
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-------------------
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-4567890123456789
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456
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(2 rows)
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SELECT q2 FROM int8_tbl EXCEPT ALL SELECT DISTINCT q1 FROM int8_tbl;
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q2
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-------------------
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-4567890123456789
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456
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4567890123456789
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(3 rows)
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SELECT q1 FROM int8_tbl EXCEPT SELECT q2 FROM int8_tbl;
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q1
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----
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(0 rows)
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SELECT q1 FROM int8_tbl EXCEPT ALL SELECT q2 FROM int8_tbl;
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q1
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------------------
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123
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4567890123456789
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(2 rows)
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SELECT q1 FROM int8_tbl EXCEPT ALL SELECT DISTINCT q2 FROM int8_tbl;
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q1
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------------------
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123
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4567890123456789
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4567890123456789
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(3 rows)
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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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f1
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----
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0
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(1 row)
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SELECT f1 FROM float8_tbl EXCEPT SELECT f1 FROM int4_tbl;
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f1
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-----------------------
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-1.2345678901234e+200
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-1004.3
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-34.84
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-1.2345678901234e-200
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(4 rows)
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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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q1
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-------------------
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123
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4567890123456789
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456
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4567890123456789
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123
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4567890123456789
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-4567890123456789
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(7 rows)
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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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q1
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------------------
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123
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4567890123456789
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(2 rows)
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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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q1
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-------------------
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123
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4567890123456789
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456
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4567890123456789
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123
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4567890123456789
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-4567890123456789
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(7 rows)
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SELECT q1 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl;
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q1
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-------------------
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-4567890123456789
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456
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(2 rows)
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SELECT q1 FROM int8_tbl UNION ALL (((SELECT q2 FROM int8_tbl EXCEPT SELECT q1 FROM int8_tbl)));
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q1
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-------------------
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123
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123
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4567890123456789
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4567890123456789
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4567890123456789
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-4567890123456789
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456
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(7 rows)
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(((SELECT q1 FROM int8_tbl UNION ALL SELECT q2 FROM int8_tbl))) EXCEPT SELECT q1 FROM int8_tbl;
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q1
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-------------------
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-4567890123456789
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456
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(2 rows)
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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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q1 | q2
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------------------+-------------------
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4567890123456789 | -4567890123456789
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123 | 456
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(2 rows)
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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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ERROR: Attribute "q2" not found
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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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q1
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------------------
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123
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4567890123456789
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(2 rows)
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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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q1 | q2
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------------------+-------------------
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123 | 456
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123 | 4567890123456789
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4567890123456789 | 123
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4567890123456789 | 4567890123456789
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4567890123456789 | -4567890123456789
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(5 rows)
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