diff options
| -rw-r--r-- | doc/src/sgml/datatype.sgml | 5 | ||||
| -rw-r--r-- | src/backend/utils/adt/cash.c | 16 | ||||
| -rw-r--r-- | src/test/regress/expected/money.out | 38 | ||||
| -rw-r--r-- | src/test/regress/sql/money.sql | 10 |
4 files changed, 61 insertions, 8 deletions
diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml index 464ce83d30e..39bbd87e677 100644 --- a/doc/src/sgml/datatype.sgml +++ b/doc/src/sgml/datatype.sgml @@ -977,6 +977,11 @@ SELECT '52093.89'::money::numeric::float8; </para> <para> + Division of a <type>money</type> value by an integer value is performed + with truncation of the fractional part towards zero. To get a rounded + result, divide by a floating-point value, or cast the <type>money</type> + value to <type>numeric</> before dividing and back to <type>money</type> + afterwards. (The latter is preferable to avoid risking precision loss.) When a <type>money</type> value is divided by another <type>money</type> value, the result is <type>double precision</type> (i.e., a pure number, not money); the currency units cancel each other out in the division. diff --git a/src/backend/utils/adt/cash.c b/src/backend/utils/adt/cash.c index b336185df7e..d329efaa9a8 100644 --- a/src/backend/utils/adt/cash.c +++ b/src/backend/utils/adt/cash.c @@ -621,7 +621,7 @@ cash_mul_flt8(PG_FUNCTION_ARGS) float8 f = PG_GETARG_FLOAT8(1); Cash result; - result = c * f; + result = rint(c * f); PG_RETURN_CASH(result); } @@ -636,7 +636,7 @@ flt8_mul_cash(PG_FUNCTION_ARGS) Cash c = PG_GETARG_CASH(1); Cash result; - result = f * c; + result = rint(f * c); PG_RETURN_CASH(result); } @@ -671,7 +671,7 @@ cash_mul_flt4(PG_FUNCTION_ARGS) float4 f = PG_GETARG_FLOAT4(1); Cash result; - result = c * f; + result = rint(c * (float8) f); PG_RETURN_CASH(result); } @@ -686,7 +686,7 @@ flt4_mul_cash(PG_FUNCTION_ARGS) Cash c = PG_GETARG_CASH(1); Cash result; - result = f * c; + result = rint((float8) f * c); PG_RETURN_CASH(result); } @@ -707,7 +707,7 @@ cash_div_flt4(PG_FUNCTION_ARGS) (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); - result = rint(c / f); + result = rint(c / (float8) f); PG_RETURN_CASH(result); } @@ -756,7 +756,7 @@ cash_div_int8(PG_FUNCTION_ARGS) (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); - result = rint(c / i); + result = c / i; PG_RETURN_CASH(result); } @@ -808,7 +808,7 @@ cash_div_int4(PG_FUNCTION_ARGS) (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); - result = rint(c / i); + result = c / i; PG_RETURN_CASH(result); } @@ -858,7 +858,7 @@ cash_div_int2(PG_FUNCTION_ARGS) (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); - result = rint(c / s); + result = c / s; PG_RETURN_CASH(result); } diff --git a/src/test/regress/expected/money.out b/src/test/regress/expected/money.out index 538235c4cc2..efb48f1acd6 100644 --- a/src/test/regress/expected/money.out +++ b/src/test/regress/expected/money.out @@ -185,6 +185,44 @@ SELECT * FROM money_data; $123.46 (1 row) +-- rounding vs. truncation in division +SELECT '878.08'::money / 11::float8; + ?column? +---------- + $79.83 +(1 row) + +SELECT '878.08'::money / 11::float4; + ?column? +---------- + $79.83 +(1 row) + +SELECT '878.08'::money / 11::int; + ?column? +---------- + $79.82 +(1 row) + +SELECT '878.08'::money / 11::smallint; + ?column? +---------- + $79.82 +(1 row) + +-- check for precision loss in division +SELECT '90000000000000099.00'::money / 10::int; + ?column? +--------------------------- + $9,000,000,000,000,009.90 +(1 row) + +SELECT '90000000000000099.00'::money / 10::smallint; + ?column? +--------------------------- + $9,000,000,000,000,009.90 +(1 row) + -- Cast int4/int8 to money SELECT 1234567890::money; money diff --git a/src/test/regress/sql/money.sql b/src/test/regress/sql/money.sql index 09b9476b706..f0db5fa4322 100644 --- a/src/test/regress/sql/money.sql +++ b/src/test/regress/sql/money.sql @@ -57,6 +57,16 @@ DELETE FROM money_data; INSERT INTO money_data VALUES ('$123.459'); SELECT * FROM money_data; +-- rounding vs. truncation in division +SELECT '878.08'::money / 11::float8; +SELECT '878.08'::money / 11::float4; +SELECT '878.08'::money / 11::int; +SELECT '878.08'::money / 11::smallint; + +-- check for precision loss in division +SELECT '90000000000000099.00'::money / 10::int; +SELECT '90000000000000099.00'::money / 10::smallint; + -- Cast int4/int8 to money SELECT 1234567890::money; SELECT 12345678901234567::money; |