diff --git a/src/backend/utils/adt/cash.c b/src/backend/utils/adt/cash.c index c92e9d5046..6515fc8ec6 100644 --- a/src/backend/utils/adt/cash.c +++ b/src/backend/utils/adt/cash.c @@ -1032,13 +1032,8 @@ Datum cash_numeric(PG_FUNCTION_ARGS) { Cash money = PG_GETARG_CASH(0); - Numeric result; + Datum result; int fpoint; - int64 scale; - int i; - Datum amount; - Datum numeric_scale; - Datum quotient; struct lconv *lconvert = PGLC_localeconv(); /* see comments about frac_digits in cash_in() */ @@ -1046,22 +1041,45 @@ cash_numeric(PG_FUNCTION_ARGS) if (fpoint < 0 || fpoint > 10) fpoint = 2; - /* compute required scale factor */ - scale = 1; - for (i = 0; i < fpoint; i++) - scale *= 10; + /* convert the integral money value to numeric */ + result = DirectFunctionCall1(int8_numeric, Int64GetDatum(money)); - /* form the result as money / scale */ - amount = DirectFunctionCall1(int8_numeric, Int64GetDatum(money)); - numeric_scale = DirectFunctionCall1(int8_numeric, Int64GetDatum(scale)); - quotient = DirectFunctionCall2(numeric_div, amount, numeric_scale); + /* scale appropriately, if needed */ + if (fpoint > 0) + { + int64 scale; + int i; + Datum numeric_scale; + Datum quotient; - /* forcibly round to exactly the intended number of digits */ - result = DatumGetNumeric(DirectFunctionCall2(numeric_round, - quotient, - Int32GetDatum(fpoint))); + /* compute required scale factor */ + scale = 1; + for (i = 0; i < fpoint; i++) + scale *= 10; + numeric_scale = DirectFunctionCall1(int8_numeric, + Int64GetDatum(scale)); - PG_RETURN_NUMERIC(result); + /* + * Given integral inputs approaching INT64_MAX, select_div_scale() + * might choose a result scale of zero, causing loss of fractional + * digits in the quotient. We can ensure an exact result by setting + * the dscale of either input to be at least as large as the desired + * result scale. numeric_round() will do that for us. + */ + numeric_scale = DirectFunctionCall2(numeric_round, + numeric_scale, + Int32GetDatum(fpoint)); + + /* Now we can safely divide ... */ + quotient = DirectFunctionCall2(numeric_div, result, numeric_scale); + + /* ... and forcibly round to exactly the intended number of digits */ + result = DirectFunctionCall2(numeric_round, + quotient, + Int32GetDatum(fpoint)); + } + + PG_RETURN_DATUM(result); } /* numeric_cash() diff --git a/src/test/regress/expected/money.out b/src/test/regress/expected/money.out index ab86595fc0..fc71a72fed 100644 --- a/src/test/regress/expected/money.out +++ b/src/test/regress/expected/money.out @@ -1,6 +1,8 @@ -- -- MONEY -- +-- Note that we assume lc_monetary has been set to C. +-- CREATE TABLE money_data (m money); INSERT INTO money_data VALUES ('123'); SELECT * FROM money_data; @@ -476,7 +478,7 @@ SELECT (-12345678901234567)::numeric::money; -$12,345,678,901,234,567.00 (1 row) --- Cast from money +-- Cast from money to numeric SELECT '12345678901234567'::money::numeric; numeric ---------------------- @@ -489,3 +491,15 @@ SELECT '-12345678901234567'::money::numeric; -12345678901234567.00 (1 row) +SELECT '92233720368547758.07'::money::numeric; + numeric +---------------------- + 92233720368547758.07 +(1 row) + +SELECT '-92233720368547758.08'::money::numeric; + numeric +----------------------- + -92233720368547758.08 +(1 row) + diff --git a/src/test/regress/sql/money.sql b/src/test/regress/sql/money.sql index 37b9ecce1f..5e746286c9 100644 --- a/src/test/regress/sql/money.sql +++ b/src/test/regress/sql/money.sql @@ -1,6 +1,8 @@ -- -- MONEY -- +-- Note that we assume lc_monetary has been set to C. +-- CREATE TABLE money_data (m money); @@ -122,6 +124,8 @@ SELECT (-1234567890)::int4::money; SELECT (-12345678901234567)::int8::money; SELECT (-12345678901234567)::numeric::money; --- Cast from money +-- Cast from money to numeric SELECT '12345678901234567'::money::numeric; SELECT '-12345678901234567'::money::numeric; +SELECT '92233720368547758.07'::money::numeric; +SELECT '-92233720368547758.08'::money::numeric;