Prepare consolidated fork preview release#2
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NumericVectorDataReader.GetValue(offset, targetType) backs the non-generic read surface (GetValue(ordinal), this[ordinal], GetValues). It always ran the boxed value through Convert.ChangeType, even when targetType already matched the column's natural type — the common case, since those APIs read using the column's ClrType. Convert.ChangeType does not early-out on same-type for IConvertible values: it dispatches through ToXxx() and re-boxes the result, so every value was boxed twice. Add a value.GetType() == targetType fast path that returns the already boxed value directly. Benchmark (read 1,000,000 rows x 3 numeric columns via GetValue, .NET 10, M4 Pro): Before: 54.50 ms, 137.3 MB allocated After: 22.73 ms, 68.7 MB allocated -58% time and -50% allocations on the object-returning path (the remaining allocation is the unavoidable single box of the object API). The typed GetFieldValue<T> path is unaffected. Behavior is unchanged: ChangeType returned the same value for same-type, and BigInteger (not IConvertible) already used this same early-out inside ChangeType.
PreparedStatement.BindParameters ran a LINQ OfType<>().Any(...) and iterated the parameters with foreach over the non-generic collection (which boxed the List<T> struct enumerator) on every command execution. Replace both with index-based loops over the typed indexer. This removes ~128 bytes and 2-3 allocations per command execution, which matters in tight parameterized-query loops. Execution time is unchanged, as the native prepare/execute dominates.
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What changed
developSkuirrels.DuckDB.NET.*preview package identitiesData.FullandBindings.FullvariantsWhy
The upstream pull requests will take time to merge and release. This provides an explicitly unofficial
1.5.4-preview.1build for testing in another open-source project without colliding with the official NuGet package IDs.Validation
net8.0andnet10.0Skuirrels.DuckDB.NET.Data.Full->Skuirrels.DuckDB.NET.Bindings.FullThe existing CA2265 span/null analyzer warning remains non-blocking.