udf.rs

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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//! UDF support
use crate::{PhysicalExpr, ScalarFunctionExpr};
use arrow::datatypes::Schema;
use datafusion_common::Result;
pub use datafusion_expr::ScalarUDF;
use std::sync::Arc;

/// Create a physical expression of the UDF.
/// This function errors when `args`' can't be coerced to a valid argument type of the UDF.
pub fn create_physical_expr(
    fun: &ScalarUDF,
    input_phy_exprs: &[Arc<dyn PhysicalExpr>],
    input_schema: &Schema,
) -> Result<Arc<dyn PhysicalExpr>> {
    let input_exprs_types = input_phy_exprs
        .iter()
        .map(|e| e.data_type(input_schema))
        .collect::<Result<Vec<_>>>()?;

    Ok(Arc::new(ScalarFunctionExpr::new(
        &fun.name,
        fun.fun.clone(),
        input_phy_exprs.to_vec(),
        (fun.return_type)(&input_exprs_types)?.as_ref(),
    )))
}