Function create_index_statement

graphlite/src/ast/parser.rs:4843–4916

Parse CREATE GRAPH INDEX [IF NOT EXISTS] statement

(tokens: &[Token])

/// Parse CREATE GRAPH INDEX [IF NOT EXISTS] statement
fn create_index_statement(tokens: &[Token]) -> IResult<&[Token], CreateIndexStatement> {
    let (tokens, _) = expect_token(Token::Create)(tokens)?;

    // Parse index type specifier
    let (tokens, index_type) = alt((
        map(
            pair(
                preceded(expect_identifier("GRAPH"), expect_identifier("INDEX")),
                opt(graph_index_type),
            ),
            |(_, gtype)| {
                IndexTypeSpecifier::Graph(gtype.unwrap_or(GraphIndexTypeSpecifier::AdjacencyList))
            },
        ),
        // Default to adjacency list if just "CREATE INDEX"
        map(expect_identifier("INDEX"), |_| {
            IndexTypeSpecifier::Graph(GraphIndexTypeSpecifier::AdjacencyList)
        }),
    ))(tokens)?;

    // Parse optional IF NOT EXISTS
    let (tokens, if_not_exists) = opt(tuple((
        expect_token(Token::If),
        expect_token(Token::Not),
        expect_token(Token::Exists),
    )))(tokens)?;
    let if_not_exists = if_not_exists.is_some();

    // Parse index name - use lenient parser to accept various tokens for better error messages
    let (tokens, name) = parse_index_name(tokens)?;

    // Parse ON table_name
    let (tokens, _) = expect_token(Token::On)(tokens)?;
    let (tokens, table) = parse_table_name(tokens)?;

    // Parse optional column list (column1, column2, ...)
    let (tokens, columns) = opt(delimited(
        expect_token(Token::LeftParen),
        separated_list1(expect_token(Token::Comma), identifier),
        expect_token(Token::RightParen),
    ))(tokens)?;

    // Parse optional USING clause
    let (tokens, _using_type) = opt(preceded(
        expect_identifier("USING"),
        alt((
            expect_identifier("IVF"),
            expect_identifier("FLAT"),
            expect_identifier("INVERTED"),
            expect_identifier("BM25"),
            expect_identifier("NGRAM"),
            expect_identifier("ADJACENCY_LIST"),
            expect_identifier("PATH_INDEX"),
            expect_identifier("REACHABILITY"),
            expect_identifier("PATTERN_INDEX"),
        )),
    ))(tokens)?;