Struct Canonicalizer 

pub struct Canonicalizer<'a> { /* private fields */ }

Canonicalizes predicates under one SQL dialect.

The dialect decides how identifiers fold, so it decides which two spellings mean one column. Build this from the dialect that parsed whatever you hand it.

Implementations

impl<'a> Canonicalizer<'a>

pub fn normalize_sql(&self, sql: &str) -> Result<String, CanonicalizeError>

Parses one SELECT and returns canonical text for its WHERE clause.

The canonical text is verified to survive being read back as itself, so a predicate whose canonical form would read as something else is rejected instead of hashed.

pub fn normalize_where_clause( &self, where_expr: Option<&Expr>, ) -> Result<String, CanonicalizeError>

Canonicalizes a parsed WHERE clause in O(n log n) time for boolean chains and O(n) otherwise.

where_expr MUST have been parsed with this canonicalizer’s dialect, which decides how names fold and which reads the canonical text back to check it.

impl<'a> Canonicalizer<'a>

pub fn new(dialect: &'a dyn Dialect) -> Self

Reads the folding rules for dialect.