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use super::super::api;
use crate::datatypes::{DataType, Field};
use crate::error::{Error, Result};
pub fn infer_descriptions(fields: &[Field]) -> Result<Vec<api::ColumnDescription>> {
fields
.iter()
.map(|field| {
let nullability = if field.is_nullable {
api::Nullability::Nullable
} else {
api::Nullability::NoNulls
};
let data_type = data_type_to(field.data_type())?;
Ok(api::ColumnDescription {
name: api::U16String::from_str(&field.name).into_vec(),
nullability,
data_type,
})
})
.collect()
}
fn data_type_to(data_type: &DataType) -> Result<api::DataType> {
Ok(match data_type {
DataType::Boolean => api::DataType::Bit,
DataType::Int16 => api::DataType::SmallInt,
DataType::Int32 => api::DataType::Integer,
DataType::Float32 => api::DataType::Float { precision: 24 },
DataType::Float64 => api::DataType::Float { precision: 53 },
DataType::FixedSizeBinary(length) => api::DataType::Binary { length: *length },
DataType::Binary | DataType::LargeBinary => api::DataType::Varbinary { length: 0 },
DataType::Utf8 | DataType::LargeUtf8 => api::DataType::Varchar { length: 0 },
other => return Err(Error::nyi(format!("{other:?} to ODBC"))),
})
}