diff options
| author | Tom Lane | 2023-03-31 20:29:55 +0000 |
|---|---|---|
| committer | Tom Lane | 2023-03-31 20:29:55 +0000 |
| commit | a2a0c7c29e47f39da905577659e66b0086b769cc (patch) | |
| tree | 9c8eb5a7f98d349edd8c60eb43984bc751c9d8e7 /src/test | |
| parent | f0d65c0eaf05d6acd3ae05cde4a31465eb3992b2 (diff) | |
Further tweaking of width_bucket() edge cases.
I realized that the third overflow case I posited in commit b0e9e4d76
actually should be handled in a different way: rather than tolerating
the idea that the quotient could round to 1, we should clamp so that
the output cannot be more than "count" when we know that the operand is
less than bound2. That being the case, we don't need an overflow-aware
increment in that code path, which leads me to revert the movement of
the pg_add_s32_overflow() call. (The diff in width_bucket_float8
might be easier to read by comparing against b0e9e4d76^.)
What's more, width_bucket_numeric also has this problem of the quotient
potentially rounding to 1, so add a clamp there too.
As before, I'm not quite convinced that a back-patch is warranted.
Discussion: https://postgr.es/m/391415.1680268470@sss.pgh.pa.us
Diffstat (limited to 'src/test')
| -rw-r--r-- | src/test/regress/expected/numeric.out | 25 | ||||
| -rw-r--r-- | src/test/regress/sql/numeric.sql | 5 |
2 files changed, 30 insertions, 0 deletions
diff --git a/src/test/regress/expected/numeric.out b/src/test/regress/expected/numeric.out index 65a9c757638..72f03c8a38a 100644 --- a/src/test/regress/expected/numeric.out +++ b/src/test/regress/expected/numeric.out @@ -1473,6 +1473,31 @@ FROM generate_series(0, 110, 10) x; 110 | 0 | 0 (12 rows) +-- Another roundoff-error hazard +SELECT width_bucket(0, -1e100::numeric, 1, 10); + width_bucket +-------------- + 10 +(1 row) + +SELECT width_bucket(0, -1e100::float8, 1, 10); + width_bucket +-------------- + 10 +(1 row) + +SELECT width_bucket(1, 1e100::numeric, 0, 10); + width_bucket +-------------- + 10 +(1 row) + +SELECT width_bucket(1, 1e100::float8, 0, 10); + width_bucket +-------------- + 10 +(1 row) + -- Check cases that could trigger overflow or underflow within the calculation SELECT oper, low, high, cnt, width_bucket(oper, low, high, cnt) FROM diff --git a/src/test/regress/sql/numeric.sql b/src/test/regress/sql/numeric.sql index 07ff98741f9..83fc386333b 100644 --- a/src/test/regress/sql/numeric.sql +++ b/src/test/regress/sql/numeric.sql @@ -909,6 +909,11 @@ FROM generate_series(0, 110, 10) x; SELECT x, width_bucket(x::float8, 100, 10, 9) as flt, width_bucket(x::numeric, 100, 10, 9) as num FROM generate_series(0, 110, 10) x; +-- Another roundoff-error hazard +SELECT width_bucket(0, -1e100::numeric, 1, 10); +SELECT width_bucket(0, -1e100::float8, 1, 10); +SELECT width_bucket(1, 1e100::numeric, 0, 10); +SELECT width_bucket(1, 1e100::float8, 0, 10); -- Check cases that could trigger overflow or underflow within the calculation SELECT oper, low, high, cnt, width_bucket(oper, low, high, cnt) |