Support spaceship operator (<=>) support (alias for IS NOT DISTINCT FROM

datafusion/sql/src/expr/binary_op.rs

@@ -53,6 +53,7 @@ impl<S: ContextProvider> SqlToRel<'_, S> {
             BinaryOperator::StringConcat => Ok(Operator::StringConcat),
             BinaryOperator::ArrowAt => Ok(Operator::ArrowAt),
             BinaryOperator::AtArrow => Ok(Operator::AtArrow),
+            BinaryOperator::Spaceship => Ok(Operator::IsNotDistinctFrom),
             _ => not_impl_err!("Unsupported SQL binary operator {op:?}"),
         }
     }

datafusion/sqllogictest/test_files/expr.slt

@@ -1565,6 +1565,62 @@ select NULL < column1 from (VALUES (true), (false)) as t;
 NULL
 NULL
 
+#### comparisons_with_spaceship_operator
+
+# Basic comparisons
+query B
+select 1 <=> 1;
+----
+true
+
+query B
+select 1 <=> 2;
+----
+false
+
+# NULL handling
+query B
+select NULL <=> NULL;
+----
+true
+
+query B
+select 1 <=> NULL;
+----
+false
+
+query B
+select NULL <=> 1;
+----
+false
+
+# Table comparisons
+query B
+select column1 <=> column2 from (VALUES (1, 1), (2, 3), (NULL, NULL)) as t;
+----
+true
+false 
+true
+
+# Sanity test - comparing <=> with equivalent expression
+query B
+SELECT 
+  (column1 <=> column2) = 
+  (IFNULL(column1, false) = IFNULL(column2, false)) AS comparison_result
+FROM (VALUES 
+  (1, 1),      -- equal values
+  (1, 2),      -- different values
+  (NULL, NULL), -- both NULL
+  (1, NULL),    -- first not NULL, second NULL
+  (NULL, 1)     -- first NULL, second not NULL
+) AS t(column1, column2);
+----
+true
+true
+true
+true
+true
+
 #### binary_mathematical_operator_with_null_lt
 
 # 1. Integer and NULL