Function test_bigquery_dialect_overrides

datafusion/sql/src/unparser/expr.rs:3659–3705

()

    #[test]
    fn test_bigquery_dialect_overrides() -> Result<()> {
        let bigquery_dialect: Arc<dyn Dialect> = Arc::new(BigQueryDialect::new());
        let unparser = Unparser::new(bigquery_dialect.as_ref());

        // date_field_extract_style: EXTRACT instead of date_part
        let expr = Expr::ScalarFunction(ScalarFunction {
            func: Arc::new(ScalarUDF::new_from_impl(
                datafusion_functions::datetime::date_part::DatePartFunc::new(),
            )),
            args: vec![lit("YEAR"), col("date_col")],
        });
        let actual = format!("{}", unparser.expr_to_sql(&expr)?);
        assert_eq!(actual, "EXTRACT(YEAR FROM `date_col`)");

        // interval_style: SQL standard instead of PostgresVerbose
        let expr = interval_year_month_lit("3 months");
        let actual = format!("{}", unparser.expr_to_sql(&expr)?);
        assert_eq!(actual, "INTERVAL '3' MONTH");

        // float64_ast_dtype: FLOAT64 instead of DOUBLE
        let expr = cast(col("a"), DataType::Float64);
        let actual = format!("{}", unparser.expr_to_sql(&expr)?);
        assert_eq!(actual, "CAST(`a` AS FLOAT64)");

        // supports_column_alias_in_table_alias: false
        assert!(!bigquery_dialect.supports_column_alias_in_table_alias());

        // utf8_cast_dtype: STRING instead of VARCHAR
        let expr = cast(col("a"), DataType::Utf8);
        let actual = format!("{}", unparser.expr_to_sql(&expr)?);
        assert_eq!(actual, "CAST(`a` AS STRING)");

        // large_utf8_cast_dtype: STRING instead of TEXT
        let expr = cast(col("a"), DataType::LargeUtf8);
        let actual = format!("{}", unparser.expr_to_sql(&expr)?);
        assert_eq!(actual, "CAST(`a` AS STRING)");

        // timestamp_cast_dtype: TIMESTAMP (no WITH TIME ZONE)
        let expr = cast(
            col("a"),
            DataType::Timestamp(TimeUnit::Microsecond, Some("+00:00".into())),
        );
        let actual = format!("{}", unparser.expr_to_sql(&expr)?);
        assert_eq!(actual, "CAST(`a` AS TIMESTAMP)");

        Ok(())
    }

    #[test]
    fn test_is_distinct_from() {