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author | Tom Lane <tgl@sss.pgh.pa.us> | 2001-10-13 23:32:34 +0000 |
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committer | Tom Lane <tgl@sss.pgh.pa.us> | 2001-10-13 23:32:34 +0000 |
commit | e482dcb0a438dfa1fcb2cb792730c00db337a834 (patch) | |
tree | 6474f00c50a7ccd98906635bd4ceabe8a5f909ab /src/backend/utils/adt/selfuncs.c | |
parent | d1c6983899df5b154c203c6f1ddf56914c0bbb30 (diff) | |
download | postgresql-e482dcb0a438dfa1fcb2cb792730c00db337a834.tar.gz postgresql-e482dcb0a438dfa1fcb2cb792730c00db337a834.zip |
Make selectivity routines cope gracefully with NaNs, infinities, and
NUMERIC values that are out of the range of 'double'. Per trouble
report from Mike Quinn.
Diffstat (limited to 'src/backend/utils/adt/selfuncs.c')
-rw-r--r-- | src/backend/utils/adt/selfuncs.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c index 57c7e854614..306758ff77e 100644 --- a/src/backend/utils/adt/selfuncs.c +++ b/src/backend/utils/adt/selfuncs.c @@ -15,7 +15,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.98 2001/10/03 18:25:59 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.99 2001/10/13 23:32:33 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -581,7 +581,18 @@ scalarineqsel(Query *root, Oid operator, bool isgt, else if (val >= high) binfrac = 1.0; else + { binfrac = (val - low) / (high - low); + /* + * Watch out for the possibility that we got a NaN + * or Infinity from the division. This can happen + * despite the previous checks, if for example + * "low" is -Infinity. + */ + if (isnan(binfrac) || + binfrac < 0.0 || binfrac > 1.0) + binfrac = 0.5; + } } else { @@ -1665,8 +1676,8 @@ icnlikejoinsel(PG_FUNCTION_ARGS) * subroutines in pg_type. * * All numeric datatypes are simply converted to their equivalent - * "double" values. XXX what about NUMERIC values that are outside - * the range of "double"? + * "double" values. (NUMERIC values that are outside the range of "double" + * are clamped to +/- HUGE_VAL.) * * String datatypes are converted by convert_string_to_scalar(), * which is explained below. The reason why this routine deals with @@ -1677,8 +1688,9 @@ icnlikejoinsel(PG_FUNCTION_ARGS) * * The several datatypes representing absolute times are all converted * to Timestamp, which is actually a double, and then we just use that - * double value. Note this will give bad results for the various "special" - * values of Timestamp --- what can we do with those? + * double value. Note this will give correct results even for the "special" + * values of Timestamp, since those are chosen to compare correctly; + * see timestamp_cmp. * * The several datatypes representing relative times (intervals) are all * converted to measurements expressed in seconds. @@ -1793,8 +1805,10 @@ convert_numeric_to_scalar(Datum value, Oid typid) case FLOAT8OID: return (double) DatumGetFloat8(value); case NUMERICOID: - return (double) DatumGetFloat8(DirectFunctionCall1(numeric_float8, - value)); + /* Note: out-of-range values will be clamped to +-HUGE_VAL */ + return (double) + DatumGetFloat8(DirectFunctionCall1(numeric_float8_no_overflow, + value)); case OIDOID: case REGPROCOID: /* we can treat OIDs as integers... */ |