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Author: jackwener

datafusion/optimizer/src/eliminate_cross_join.rs

@@ -535,6 +535,21 @@ mod tests {
     }
 
     #[test]
+    /// ```txt
+    /// filter: a.id = b.id and a.id = c.id
+    ///   cross_join a (bc)
+    ///     cross_join b c
+    /// ```
+    /// Without reorder, it will be
+    /// ```txt
+    ///   inner_join a (bc) on a.id = b.id and a.id = c.id
+    ///     cross_join b c
+    /// ```
+    /// Reorder it to be
+    /// ```txt
+    ///   inner_join (ab)c and a.id = c.id
+    ///     inner_join a b on a.id = b.id
+    /// ```
     fn reduce_cross_not_possible_simple() -> Result<()> {
         let t1 = test_table_scan_with_name("t1")?;
         let t2 = test_table_scan_with_name("t2")?;