ShardKeyExtractor

Trait for extracting shard key values from a record.

Records must implement this trait to enable shard-aware routing. Returns a SmallVec of (column_name, typed_value) pairs for shard key columns.

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Performance

• Returns ShardKeyValues (SmallVec) which is stack-allocated for up to 4 columns
• Use typed variants (Int, Long, Float, Double) when possible to avoid string parsing overhead
• The String variants are for string/char columns, and specialized variants (Date, Ipv4, Decimal) handle formatted types
• Use the smallvec! macro for convenient construction

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Example

use smallvec::smallvec;
use gpudb_api::{ShardKeyExtractor, ShardKeyValue, ShardKeyValues};

impl ShardKeyExtractor for MyRecord {
    fn shard_key_values(&self) -> ShardKeyValues<'_> {
        smallvec![
            ("id", ShardKeyValue::Int(self.id)),
            ("region", ShardKeyValue::String(&self.region)),
        ]
    }
}