Function expr_to_sql_ok

datafusion/sql/src/unparser/expr.rs:2006–2511

()

    #[test]
    fn expr_to_sql_ok() -> Result<()> {
        let dummy_schema = Schema::new(vec![Field::new("a", DataType::Int32, false)]);
        #[expect(deprecated)]
        let dummy_logical_plan = table_scan(Some("t"), &dummy_schema, None)?
            .project(vec![Expr::Wildcard {
                qualifier: None,
                options: Box::new(WildcardOptions::default()),
            }])?
            .filter(col("a").eq(lit(1)))?
            .build()?;

        let tests: Vec<(Expr, &str)> = vec![
            ((col("a") + col("b")).gt(lit(4)), r#"((a + b) > 4)"#),
            (
                Expr::Column(Column {
                    relation: Some(TableReference::partial("a", "b")),
                    name: "c".to_string(),
                    spans: Spans::new(),
                })
                .gt(lit(4)),
                r#"(b.c > 4)"#,
            ),
            (
                case(col("a"))
                    .when(lit(1), lit(true))
                    .when(lit(0), lit(false))
                    .otherwise(lit(ScalarValue::Null))?,
                r#"CASE a WHEN 1 THEN true WHEN 0 THEN false ELSE NULL END"#,
            ),
            (
                when(col("a").is_null(), lit(true)).otherwise(lit(false))?,
                r#"CASE WHEN a IS NULL THEN true ELSE false END"#,
            ),
            (
                when(col("a").is_not_null(), lit(true)).otherwise(lit(false))?,
                r#"CASE WHEN a IS NOT NULL THEN true ELSE false END"#,
            ),
            (
                Expr::Cast(Cast::new(Box::new(col("a")), DataType::Date64)),
                r#"CAST(a AS DATETIME)"#,
            ),
            (
                Expr::Cast(Cast::new(
                    Box::new(col("a")),
                    DataType::Timestamp(TimeUnit::Nanosecond, Some("+08:00".into())),
                )),
                r#"CAST(a AS TIMESTAMP WITH TIME ZONE)"#,
            ),
            (
                Expr::Cast(Cast::new(
                    Box::new(col("a")),
                    DataType::Timestamp(TimeUnit::Millisecond, None),
                )),
                r#"CAST(a AS TIMESTAMP)"#,
            ),
            (
                Expr::Cast(Cast::new(Box::new(col("a")), DataType::UInt32)),
                r#"CAST(a AS INTEGER UNSIGNED)"#,