`qualify_columns`: expand_stars does not expand SELECT * into individual columns

[karakanb]

qualify_columns() with expand_stars: true does not seem to rewrite SELECT * into the individual columns from the provided schema. The AST is returned unchanged.

sqlglot repro

# /// script
# requires-python = ">=3.9"
# dependencies = ["sqlglot>=26.0"]
# ///
from sqlglot import exp
from sqlglot.optimizer import optimize
from sqlglot.optimizer.qualify import qualify

query = "SELECT * FROM users"
schema = {"users": {"id": "INT64", "name": "TEXT", "email": "TEXT"}}
print(f"Query: {query}\n")

optimized = optimize(exp.maybe_parse(query, dialect="bigquery"), schema, dialect="bigquery", rules=(qualify,))
select = optimized.find(exp.Select)
col_names = [e.alias_or_name for e in select.expressions]
print(f"column names: {col_names}")

polyglot repro

use polyglot_sql::{self as pgsql, DialectType, MappingSchema, Schema};
use polyglot_sql::expressions::DataType;

fn main() {
    let query = "SELECT * FROM users";
    println!("Query: {query}\n");

    let exprs = pgsql::parse(query, DialectType::BigQuery).unwrap();

    // Build schema with known columns
    let mut schema = MappingSchema::with_dialect(DialectType::BigQuery);
    schema.add_table("users", &[
        ("id".into(), DataType::Int { length: None, integer_spelling: false }),
        ("name".into(), DataType::Text),
        ("email".into(), DataType::Text),
    ], None).unwrap();

    // qualify_columns has expand_stars=true by default
    let options = pgsql::optimizer::qualify_columns::QualifyColumnsOptions::new()
        .with_expand_stars(true)
        .with_dialect(DialectType::BigQuery);
    let qualified = pgsql::optimizer::qualify_columns::qualify_columns(
        exprs[0].clone(), &schema, &options,
    ).unwrap();

    let sql = pgsql::generate(&qualified, DialectType::BigQuery).unwrap();
    println!("after qualify_columns: {sql}");

    let col_names = pgsql::ast_transforms::get_column_names(&qualified);
    println!("get_column_names: {col_names:?}");
}

sqlglot rewrites SELECT * into SELECT users.id, users.name, users.email when a schema is provided. Please let me know if I am missing how to use the library here.

[tobilg]

Thanks, I‘ll have a look!

[karakanb]

By the way I am creating these issues as I go with as simple reproduction cases as I can think of to identify gaps. Please do not feel any sort of pressure around any of this, I think this is a very cool project, thanks for building it!

[tobilg]

No worries, they are really helpful, thanks a lot! I'll try my best to keep up, can take a few days sometimes though...

[tobilg]

Thanks for reporting, this will be fixed in version 0.1.7.