diff --git a/src/postgres/math_udfs.rs b/src/postgres/math_udfs.rs
index f8e632c..92f7974 100644
--- a/src/postgres/math_udfs.rs
+++ b/src/postgres/math_udfs.rs
@@ -119,22 +119,56 @@ pub fn sind(args: &[ArrayRef]) -> Result<ArrayRef> {
 }
 
 /// Inverse tangent, result in degrees.
-pub fn atand(args: &[ArrayRef]) -> Result<ArrayRef> {
-    let values = datafusion::common::cast::as_float64_array(&args[0])?;
-    let mut float64array_builder = Float64Array::builder(args[0].len());
+#[derive(Debug)]
+pub struct Atand {
+    signature: Signature,
+}
 
-    values.iter().try_for_each(|value| {
-        if let Some(value) = value {
-            let result = value.atan().to_degrees();
-            float64array_builder.append_value(result);
-            Ok::<(), DataFusionError>(())
-        } else {
-            float64array_builder.append_null();
-            Ok::<(), DataFusionError>(())
+impl Atand {
+    pub fn new() -> Self {
+        Self {
+            signature: Signature::uniform(1, vec![Float64], Volatility::Immutable),
         }
-    })?;
+    }
+}
 
-    Ok(Arc::new(float64array_builder.finish()) as ArrayRef)
+impl ScalarUDFImpl for Atand {
+    fn as_any(&self) -> &dyn std::any::Any {
+        self
+    }
+
+    fn name(&self) -> &str {
+        "atand"
+    }
+
+    fn signature(&self) -> &Signature {
+        &self.signature
+    }
+
+    fn return_type(&self, _arg_types: &[DataType]) -> Result<DataType> {
+        Ok(Float64)
+    }
+
+    fn invoke(&self, args: &[ColumnarValue]) -> Result<ColumnarValue> {
+        let args = ColumnarValue::values_to_arrays(args)?;
+        let values = datafusion::common::cast::as_float64_array(&args[0])?;
+        let mut float64array_builder = Float64Array::builder(args[0].len());
+
+        values.iter().try_for_each(|value| {
+            if let Some(value) = value {
+                let result = value.atan().to_degrees();
+                float64array_builder.append_value(result);
+                Ok::<(), DataFusionError>(())
+            } else {
+                float64array_builder.append_null();
+                Ok::<(), DataFusionError>(())
+            }
+        })?;
+
+        Ok(ColumnarValue::Array(
+            Arc::new(float64array_builder.finish()) as ArrayRef,
+        ))
+    }
 }
 
 /// Tangent, argument in degrees.
diff --git a/src/postgres/mod.rs b/src/postgres/mod.rs
index 5bd6f9b..bd227a1 100644
--- a/src/postgres/mod.rs
+++ b/src/postgres/mod.rs
@@ -10,7 +10,7 @@ use datafusion::physical_expr::functions::make_scalar_function;
 use datafusion::prelude::SessionContext;
 
 use crate::postgres::math_udfs::{
-    acosd, asind, atand, cosd, cotd, sind, Ceiling, Div, Erf, Erfc, RandomNormal, Tand,
+    acosd, asind, cosd, cotd, sind, Atand, Ceiling, Div, Erf, Erfc, RandomNormal, Tand,
 };
 use crate::postgres::network_udfs::{
     broadcast, family, host, hostmask, inet_merge, inet_same_family, masklen, netmask, network,
@@ -32,7 +32,7 @@ fn register_math_udfs(ctx: &SessionContext) -> Result<()> {
     register_cotd(ctx);
     register_asind(ctx);
     register_sind(ctx);
-    register_atand(ctx);
+    ctx.register_udf(ScalarUDF::from(Atand::new()));
     ctx.register_udf(ScalarUDF::from(Tand::new()));
     ctx.register_udf(ScalarUDF::from(Ceiling::new()));
     ctx.register_udf(ScalarUDF::from(Div::new()));
@@ -107,19 +107,6 @@ fn register_cotd(ctx: &SessionContext) {
     ctx.register_udf(cotd_udf);
 }
 
-fn register_atand(ctx: &SessionContext) {
-    let atand_udf = make_scalar_function(atand);
-    let return_type: ReturnTypeFunction = Arc::new(move |_| Ok(Arc::new(Float64)));
-    let atand_udf = ScalarUDF::new(
-        "atand",
-        &Signature::uniform(1, vec![Float64], Volatility::Immutable),
-        &return_type,
-        &atand_udf,
-    );
-
-    ctx.register_udf(atand_udf);
-}
-
 fn register_network_udfs(ctx: &SessionContext) -> Result<()> {
     register_broadcast(ctx);
     register_family(ctx);