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542320c2bd
The previous coding in get_const_expr() tried to avoid quoting integer, float, and numeric literals if at all possible. While that looks nice, it means that dumped expressions might re-parse to something that's semantically equivalent but not the exact same parsetree; for example a FLOAT8 constant would re-parse as a NUMERIC constant with a cast to FLOAT8. Though the result would be the same after constant-folding, this is problematic in certain contexts. In particular, Jeff Davis pointed out that this could cause unexpected failures in ALTER INHERIT operations because of child tables having not-exactly-equivalent CHECK expressions. Therefore, favor correctness over legibility and dump such constants in quotes except in the limited cases where they'll be interpreted as the same type even without any casting. This results in assorted small changes in the regression test outputs, and will affect display of user-defined views and rules similarly. The odds of that causing problems in the field seem non-negligible; given the lack of previous complaints, it seems best not to change this in the back branches.
92 lines
1.8 KiB
Plaintext
92 lines
1.8 KiB
Plaintext
-- float8 check
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CREATE TABLE float8tmp (a float8);
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\copy float8tmp from 'data/float8.data'
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SET enable_seqscan=on;
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SELECT count(*) FROM float8tmp WHERE a < -1890.0;
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count
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-------
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237
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(1 row)
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SELECT count(*) FROM float8tmp WHERE a <= -1890.0;
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count
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-------
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238
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(1 row)
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SELECT count(*) FROM float8tmp WHERE a = -1890.0;
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count
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-------
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1
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(1 row)
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SELECT count(*) FROM float8tmp WHERE a >= -1890.0;
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count
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-------
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307
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(1 row)
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SELECT count(*) FROM float8tmp WHERE a > -1890.0;
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count
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-------
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306
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(1 row)
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SELECT a, a <-> '-1890.0' FROM float8tmp ORDER BY a <-> '-1890.0' LIMIT 3;
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a | ?column?
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--------------+------------
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-1890 | 0
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-2003.634512 | 113.634512
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-1769.73634 | 120.26366
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(3 rows)
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CREATE INDEX float8idx ON float8tmp USING gist ( a );
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SET enable_seqscan=off;
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SELECT count(*) FROM float8tmp WHERE a < -1890.0::float8;
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count
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-------
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237
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(1 row)
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SELECT count(*) FROM float8tmp WHERE a <= -1890.0::float8;
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count
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-------
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238
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(1 row)
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SELECT count(*) FROM float8tmp WHERE a = -1890.0::float8;
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count
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-------
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1
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(1 row)
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SELECT count(*) FROM float8tmp WHERE a >= -1890.0::float8;
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count
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-------
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307
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(1 row)
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SELECT count(*) FROM float8tmp WHERE a > -1890.0::float8;
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count
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-------
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306
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(1 row)
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EXPLAIN (COSTS OFF)
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SELECT a, a <-> '-1890.0' FROM float8tmp ORDER BY a <-> '-1890.0' LIMIT 3;
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QUERY PLAN
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-----------------------------------------------------
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Limit
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-> Index Only Scan using float8idx on float8tmp
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Order By: (a <-> '-1890'::double precision)
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(3 rows)
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SELECT a, a <-> '-1890.0' FROM float8tmp ORDER BY a <-> '-1890.0' LIMIT 3;
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a | ?column?
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--------------+------------
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-1890 | 0
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-2003.634512 | 113.634512
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-1769.73634 | 120.26366
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(3 rows)
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