ansi.rs

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// to you under the Apache License, Version 2.0 (the
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// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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use crate::dialect::Dialect;

/// A [`Dialect`] for [ANSI SQL](https://en.wikipedia.org/wiki/SQL:2011).
#[derive(Debug, Default, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
pub struct AnsiDialect {}

impl Dialect for AnsiDialect {
    fn is_identifier_start(&self, ch: char) -> bool {
        ch.is_ascii_lowercase() || ch.is_ascii_uppercase()
    }

    fn is_identifier_part(&self, ch: char) -> bool {
        ch.is_ascii_lowercase() || ch.is_ascii_uppercase() || ch.is_ascii_digit() || ch == '_'
    }

    fn require_interval_qualifier(&self) -> bool {
        true
    }

    /// The SQL standard explicitly states that block comments nest.
    fn supports_nested_comments(&self) -> bool {
        true
    }

    fn supports_is_json_predicate(&self) -> bool {
        true
    }
}