Detailed change list:
- Splitting out the narrow part of "class Decimal" into a separate class TDecimal64
- Adding a method TDecimal64::toSInt64Round()
- Reusing the method TDecimal64::toSInt64Round() in:
* Func_cast_signed::getIntVal()
* Func_char::getStrVal()
* Func_elt::getStrVal()
* makedate()
* Func_maketime::getStrVal()
Note, reusing this method in Func_char::getStrVal() also fixed this bug:
MCOL-4634 CHAR(negativeWideDecimal) is not like InnoDB
because the old code handled negative wide decimal values
in a wrong way.
- Adding a new class TDecimal128 for symmetry.
Moving a few wide decimal methods and constexpr's from Decimal to TDecimal128.
The new class TDecimal128 does not do much at this point yet.
Later we should be able to use TDecimal128 vs TDecimal64 in templates.
This change fixes:
MCOL-4462 CAST(varchar_expr AS DECIMAL(M,N)) returns a wrong result
MCOL-4500 Bit functions processing throws internally trying to cast char into decimal representation
MCOL-4532 CAST(AS DECIMAL) returns a garbage for large values
Also, this change makes string-to-decimal conversion 5-10 times faster,
depending on exact data.
Performance implemenent is achieved by the fact that (unlike in the old
implementation), the new version does not do any "string" object copying.
MCOL-4409 This patch combines VDecimal and Decimal and makes
IDB_Decimal an alias for the result class
MCOL-4409 More boilerplate reduction in Func_mod
Removed couple TSInt128::toType() methods
1. In TupleAggregateStep::configDeliveredRowGroup(), use
jobInfo.projectionCols instead of jobInfo.nonConstCols
for setting scale and precision if the source column is
wide decimal.
2. Tighten rules for wide decimal processing. Specifically:
a. Replace (precision > INT64MAXPRECISION) checks with
(precision > INT64MAXPRECISION && precision <= INT128MAXPRECISION)
b. At places where (colWidth == MAXDECIMALWIDTH) is not enough to
determine if a column is wide decimal or not, also add a check on
type being DECIMAL/UDECIMAL.
DOUBLE typecast was not supported and the failure detection caused a
crash.
This patch adds support for DOUBLE typecast and fixes the crash caused
when a non-supported function is detected as part of an arithmatic.
For the initial BLOB/TEXT pull request we put them in the same bucket as
VARBINARY, forcing many functions to be disabled. This patch enables the
same TEXT function support as VARCHAR.