diff --git a/src/common/function/src/scalars/timestamp.rs b/src/common/function/src/scalars/timestamp.rs
index bc4662f08e91..17fb9a2443ba 100644
--- a/src/common/function/src/scalars/timestamp.rs
+++ b/src/common/function/src/scalars/timestamp.rs
@@ -12,17 +12,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use std::sync::Arc;
-mod from_unixtime;
-
-use from_unixtime::FromUnixtimeFunction;
-
 use crate::scalars::function_registry::FunctionRegistry;
 
 pub(crate) struct TimestampFunction;
 
 impl TimestampFunction {
-    pub fn register(registry: &FunctionRegistry) {
-        registry.register(Arc::new(FromUnixtimeFunction::default()));
-    }
+    pub fn register(_registry: &FunctionRegistry) {}
 }
diff --git a/src/common/function/src/scalars/timestamp/from_unixtime.rs b/src/common/function/src/scalars/timestamp/from_unixtime.rs
deleted file mode 100644
index b38fbb6749d8..000000000000
--- a/src/common/function/src/scalars/timestamp/from_unixtime.rs
+++ /dev/null
@@ -1,133 +0,0 @@
-// Copyright 2023 Greptime Team
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-//! from_unixtime function.
-/// TODO(dennis) It can be removed after we upgrade datafusion.
-use std::fmt;
-use std::sync::Arc;
-
-use common_query::error::{
-    ArrowComputeSnafu, IntoVectorSnafu, Result, TypeCastSnafu, UnsupportedInputDataTypeSnafu,
-};
-use common_query::prelude::{Signature, Volatility};
-use datatypes::arrow::compute;
-use datatypes::arrow::datatypes::{DataType as ArrowDatatype, Int64Type};
-use datatypes::data_type::DataType;
-use datatypes::prelude::ConcreteDataType;
-use datatypes::vectors::{TimestampMillisecondVector, VectorRef};
-use snafu::ResultExt;
-
-use crate::scalars::function::{Function, FunctionContext};
-
-#[derive(Clone, Debug, Default)]
-pub struct FromUnixtimeFunction;
-
-const NAME: &str = "from_unixtime";
-
-impl Function for FromUnixtimeFunction {
-    fn name(&self) -> &str {
-        NAME
-    }
-
-    fn return_type(&self, _input_types: &[ConcreteDataType]) -> Result<ConcreteDataType> {
-        Ok(ConcreteDataType::timestamp_millisecond_datatype())
-    }
-
-    fn signature(&self) -> Signature {
-        Signature::uniform(
-            1,
-            vec![ConcreteDataType::int64_datatype()],
-            Volatility::Immutable,
-        )
-    }
-
-    fn eval(&self, _func_ctx: FunctionContext, columns: &[VectorRef]) -> Result<VectorRef> {
-        match columns[0].data_type() {
-            ConcreteDataType::Int64(_) => {
-                let array = columns[0].to_arrow_array();
-                // Our timestamp vector's time unit is millisecond
-                let array = compute::multiply_scalar_dyn::<Int64Type>(&array, 1000i64)
-                    .context(ArrowComputeSnafu)?;
-
-                let arrow_datatype = &self.return_type(&[]).unwrap().as_arrow_type();
-                Ok(Arc::new(
-                    TimestampMillisecondVector::try_from_arrow_array(
-                        compute::cast(&array, arrow_datatype).context(TypeCastSnafu {
-                            typ: ArrowDatatype::Int64,
-                        })?,
-                    )
-                    .context(IntoVectorSnafu {
-                        data_type: arrow_datatype.clone(),
-                    })?,
-                ))
-            }
-            _ => UnsupportedInputDataTypeSnafu {
-                function: NAME,
-                datatypes: columns.iter().map(|c| c.data_type()).collect::<Vec<_>>(),
-            }
-            .fail(),
-        }
-    }
-}
-
-impl fmt::Display for FromUnixtimeFunction {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "FROM_UNIXTIME")
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use common_query::prelude::TypeSignature;
-    use datatypes::value::Value;
-    use datatypes::vectors::Int64Vector;
-
-    use super::*;
-
-    #[test]
-    fn test_from_unixtime() {
-        let f = FromUnixtimeFunction::default();
-        assert_eq!("from_unixtime", f.name());
-        assert_eq!(
-            ConcreteDataType::timestamp_millisecond_datatype(),
-            f.return_type(&[]).unwrap()
-        );
-
-        assert!(matches!(f.signature(),
-                         Signature {
-                             type_signature: TypeSignature::Uniform(1, valid_types),
-                             volatility: Volatility::Immutable
-                         } if  valid_types == vec![ConcreteDataType::int64_datatype()]
-        ));
-
-        let times = vec![Some(1494410783), None, Some(1494410983)];
-        let args: Vec<VectorRef> = vec![Arc::new(Int64Vector::from(times.clone()))];
-
-        let vector = f.eval(FunctionContext::default(), &args).unwrap();
-        assert_eq!(3, vector.len());
-        for (i, t) in times.iter().enumerate() {
-            let v = vector.get(i);
-            if i == 1 {
-                assert_eq!(Value::Null, v);
-                continue;
-            }
-            match v {
-                Value::Timestamp(ts) => {
-                    assert_eq!(ts.value(), t.unwrap() * 1000);
-                }
-                _ => unreachable!(),
-            }
-        }
-    }
-}