perf(sql): improve double-to-decimal conversion with bulk multiply#6799
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bluestreak01 merged 2 commits intomasterfrom Feb 22, 2026
Merged
perf(sql): improve double-to-decimal conversion with bulk multiply#6799bluestreak01 merged 2 commits intomasterfrom
bluestreak01 merged 2 commits intomasterfrom
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Add a bulk initialization method that sets a decimal to digits * 10^power using a single wide multiply. This replaces the digit-by-digit loop pattern in doubleToDecimal() that performed up to 17 long divisions for digit extraction and 17 wide additions. The method handles negative powers by storing the digits directly with scale = -power, so callers can represent fractions without a separate setScale() call. Both doubleToDecimal() overloads in Numbers.java now use ofDigitsAndPower() instead of the ofZero() + loop + setScale() pattern. Co-Authored-By: Claude Opus 4.6 <[email protected]>
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bluestreak01
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Summary
ofDigitsAndPower(long digits, int power)to theDecimalinterface, replacing the digit-by-digit loop indoubleToDecimal()with a single wide multiply.Benchmark results
Decimal64 is 1.8x faster, Decimal128 is 2.2x faster, Decimal256 is 2.8x faster. The three types converge to roughly the same cost since the single multiply dominates and the word-width difference matters less for one operation than for 17. VARCHAR is an unrelated control.
Test plan
NumbersDoubleToDecimalTestCastDoubleToDecimalFunctionFactoryTestCastTest🤖 Generated with Claude Code