sqlx_exasol_impl/
column.rs

1use std::{borrow::Cow, fmt::Display};
2
3use serde::{Deserialize, Deserializer, Serialize};
4use sqlx_core::{column::Column, database::Database, ext::ustr::UStr};
5
6use crate::{database::Exasol, type_info::ExaTypeInfo};
7
8/// Implementor of [`Column`].
9#[derive(Debug, Clone, Deserialize, Serialize)]
10#[serde(rename_all = "camelCase")]
11pub struct ExaColumn {
12    #[serde(default)]
13    pub(crate) ordinal: usize,
14    #[serde(deserialize_with = "ExaColumn::lowercase_name")]
15    pub(crate) name: UStr,
16    pub(crate) data_type: ExaTypeInfo,
17}
18
19impl ExaColumn {
20    fn lowercase_name<'de, D>(deserializer: D) -> Result<UStr, D::Error>
21    where
22        D: Deserializer<'de>,
23    {
24        /// Intermediate type used to take advantage of [`Cow`] borrowed deserialization when
25        /// possible.
26        ///
27        /// In regular usage, an owned buffer is used and a borrowed [`str`] could be
28        /// used, but for offline query deserialization a reader seems to be used and the buffer is
29        /// shortlived, hence a string slice would fail deserialization.
30        #[derive(Deserialize)]
31        struct CowStr<'a>(#[serde(borrow)] Cow<'a, str>);
32
33        CowStr::deserialize(deserializer)
34            .map(|c| c.0.to_lowercase())
35            .map(From::from)
36    }
37}
38
39impl Display for ExaColumn {
40    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
41        write!(f, "{}: {}", self.name, self.data_type)
42    }
43}
44
45impl Column for ExaColumn {
46    type Database = Exasol;
47
48    fn ordinal(&self) -> usize {
49        self.ordinal
50    }
51
52    fn name(&self) -> &str {
53        &self.name
54    }
55
56    fn type_info(&self) -> &<Self::Database as Database>::TypeInfo {
57        &self.data_type
58    }
59}
sqlx_exasol_impl/column.rs

sqlx_exasol_impl/
column.rs
