diff --git a/src/ast/values.rs b/src/ast/values.rs
index e5cf8ac8..dee3dbf0 100644
--- a/src/ast/values.rs
+++ b/src/ast/values.rs
@@ -45,6 +45,8 @@ pub enum Value<'a> {
     Int32(Option<i32>),
     /// 64-bit signed integer.
     Int64(Option<i64>),
+    /// 32-bit unsigned integer.
+    UnsignedInt32(Option<u32>),
     /// 32-bit floating point.
     Float(Option<f32>),
     /// 64-bit floating point.
@@ -112,6 +114,7 @@ impl<'a> fmt::Display for Value<'a> {
         let res = match self {
             Value::Int32(val) => val.map(|v| write!(f, "{}", v)),
             Value::Int64(val) => val.map(|v| write!(f, "{}", v)),
+            Value::UnsignedInt32(val) => val.map(|v| write!(f, "{}", v)),
             Value::Float(val) => val.map(|v| write!(f, "{}", v)),
             Value::Double(val) => val.map(|v| write!(f, "{}", v)),
             Value::Text(val) => val.as_ref().map(|v| write!(f, "\"{}\"", v)),
@@ -161,6 +164,7 @@ impl<'a> From<Value<'a>> for serde_json::Value {
         let res = match pv {
             Value::Int32(i) => i.map(|i| serde_json::Value::Number(Number::from(i))),
             Value::Int64(i) => i.map(|i| serde_json::Value::Number(Number::from(i))),
+            Value::UnsignedInt32(u) => u.map(|u| serde_json::Value::Number(Number::from(u))),
             Value::Float(f) => f.map(|f| match Number::from_f64(f as f64) {
                 Some(number) => serde_json::Value::Number(number),
                 None => serde_json::Value::Null,
@@ -222,6 +226,14 @@ impl<'a> Value<'a> {
         Value::Int64(Some(value.into()))
     }
 
+    /// Creates a new 32-bit signed integer.
+    pub fn uint32<I>(value: I) -> Self
+    where
+        I: Into<u32>,
+    {
+        Value::UnsignedInt32(Some(value.into()))
+    }
+
     /// Creates a new 32-bit signed integer.
     pub fn integer<I>(value: I) -> Self
     where
@@ -344,6 +356,7 @@ impl<'a> Value<'a> {
         match self {
             Value::Int32(i) => i.is_none(),
             Value::Int64(i) => i.is_none(),
+            Value::UnsignedInt32(u) => u.is_none(),
             Value::Float(i) => i.is_none(),
             Value::Double(i) => i.is_none(),
             Value::Text(t) => t.is_none(),
@@ -442,6 +455,11 @@ impl<'a> Value<'a> {
         matches!(self, Value::Int64(_))
     }
 
+    /// `true` if the `Value` is a 64-bit signed integer.
+    pub const fn is_uint32(&self) -> bool {
+        matches!(self, Value::UnsignedInt32(_))
+    }
+
     /// `true` if the `Value` is a signed integer.
     pub const fn is_integer(&self) -> bool {
         matches!(self, Value::Int32(_) | Value::Int64(_))
@@ -463,6 +481,14 @@ impl<'a> Value<'a> {
         }
     }
 
+    /// Returns an `i32` if the value is a 32-bit signed integer, otherwise `None`.
+    pub const fn as_uint32(&self) -> Option<u32> {
+        match self {
+            Value::UnsignedInt32(i) => *i,
+            _ => None,
+        }
+    }
+
     /// Returns an `i64` if the value is a signed integer, otherwise `None`.
     pub fn as_integer(&self) -> Option<i64> {
         match self {
@@ -526,6 +552,7 @@ impl<'a> Value<'a> {
             // For schemas which don't tag booleans
             Value::Int32(Some(i)) if *i == 0 || *i == 1 => true,
             Value::Int64(Some(i)) if *i == 0 || *i == 1 => true,
+            Value::UnsignedInt32(Some(i)) if *i == 0 || *i == 1 => true,
             _ => false,
         }
     }
@@ -537,6 +564,7 @@ impl<'a> Value<'a> {
             // For schemas which don't tag booleans
             Value::Int32(Some(i)) if *i == 0 || *i == 1 => Some(*i == 1),
             Value::Int64(Some(i)) if *i == 0 || *i == 1 => Some(*i == 1),
+            Value::UnsignedInt32(Some(i)) if *i == 0 || *i == 1 => Some(*i == 1),
             _ => None,
         }
     }
@@ -662,6 +690,7 @@ impl<'a> Value<'a> {
 
 value!(val: i64, Int64, val);
 value!(val: i32, Int32, val);
+value!(val: u32, UnsignedInt32, val);
 value!(val: bool, Boolean, val);
 value!(val: &'a str, Text, val.into());
 value!(val: String, Text, val.into());
@@ -708,6 +737,16 @@ impl<'a> TryFrom<Value<'a>> for i32 {
     }
 }
 
+impl<'a> TryFrom<Value<'a>> for u32 {
+    type Error = Error;
+
+    fn try_from(value: Value<'a>) -> Result<u32, Self::Error> {
+        value
+            .as_uint32()
+            .ok_or_else(|| Error::builder(ErrorKind::conversion("Not a u32")).build())
+    }
+}
+
 #[cfg(feature = "bigdecimal")]
 impl<'a> TryFrom<Value<'a>> for BigDecimal {
     type Error = Error;
@@ -931,6 +970,13 @@ mod tests {
         assert_eq!(values, vec![1]);
     }
 
+    #[test]
+    fn a_parameterized_value_of_uints32_can_be_converted_into_a_vec() {
+        let pv = Value::array(vec![1_u32]);
+        let values: Vec<u32> = pv.into_vec().expect("convert into Vec<i64>");
+        assert_eq!(values, vec![1]);
+    }
+
     #[test]
     fn a_parameterized_value_of_reals_can_be_converted_into_a_vec() {
         let pv = Value::array(vec![1.0]);
diff --git a/src/connector/mssql/conversion.rs b/src/connector/mssql/conversion.rs
index aa7d681d..0ab7357a 100644
--- a/src/connector/mssql/conversion.rs
+++ b/src/connector/mssql/conversion.rs
@@ -13,6 +13,7 @@ impl<'a> IntoSql<'a> for &'a Value<'a> {
         match self {
             Value::Int32(val) => val.into_sql(),
             Value::Int64(val) => val.into_sql(),
+            Value::UnsignedInt32(val) => val.map(|val| val as i64).into_sql(),
             Value::Float(val) => val.into_sql(),
             Value::Double(val) => val.into_sql(),
             Value::Text(val) => val.as_deref().into_sql(),
diff --git a/src/connector/mysql/conversion.rs b/src/connector/mysql/conversion.rs
index 2dea3178..c953ea7a 100644
--- a/src/connector/mysql/conversion.rs
+++ b/src/connector/mysql/conversion.rs
@@ -23,6 +23,7 @@ pub fn conv_params(params: &[Value<'_>]) -> crate::Result<my::Params> {
             let res = match pv {
                 Value::Int32(i) => i.map(|i| my::Value::Int(i as i64)),
                 Value::Int64(i) => i.map(my::Value::Int),
+                Value::UnsignedInt32(u) => u.map(|u| my::Value::UInt(u as u64)),
                 Value::Float(f) => f.map(my::Value::Float),
                 Value::Double(f) => f.map(my::Value::Double),
                 Value::Text(s) => s.clone().map(|s| my::Value::Bytes((&*s).as_bytes().to_vec())),
@@ -110,7 +111,7 @@ impl TypeIdentifier for my::Column {
 
         let is_unsigned = self.flags().intersects(ColumnFlags::UNSIGNED_FLAG);
 
-        // https://dev.mysql.com/doc/internals/en/binary-protocol-value.html#packet-ProtocolBinary
+        // https://dev.mysql.com/doc/dev/mysql-server/latest/page_protocol_binary_resultset.html
         // MYSQL_TYPE_TINY  = i8
         // MYSQL_TYPE_SHORT = i16
         // MYSQL_TYPE_YEAR  = i16
@@ -129,16 +130,20 @@ impl TypeIdentifier for my::Column {
     fn is_int64(&self) -> bool {
         use ColumnType::*;
 
+        // https://dev.mysql.com/doc/dev/mysql-server/latest/page_protocol_binary_resultset.html
+        // MYSQL_TYPE_LONGLONG = i64
+        matches!(self.column_type(), MYSQL_TYPE_LONGLONG)
+    }
+
+    fn is_uint32(&self) -> bool {
+        use ColumnType::*;
+
         let is_unsigned = self.flags().intersects(ColumnFlags::UNSIGNED_FLAG);
 
-        // https://dev.mysql.com/doc/internals/en/binary-protocol-value.html#packet-ProtocolBinary
-        // MYSQL_TYPE_LONGLONG = i64
-        // UNSIGNED MYSQL_TYPE_LONG = u32
+        // https://dev.mysql.com/doc/dev/mysql-server/latest/page_protocol_binary_resultset.html
+        // UNSIGNED MYSQL_TYPE_LONG  = u32
         // UNSIGNED MYSQL_TYPE_INT24 = u32
-        matches!(
-            (self.column_type(), is_unsigned),
-            (MYSQL_TYPE_LONGLONG, _) | (MYSQL_TYPE_LONG, true) | (MYSQL_TYPE_INT24, true)
-        )
+        is_unsigned && matches!(self.column_type(), MYSQL_TYPE_LONG | MYSQL_TYPE_INT24)
     }
 
     fn is_datetime(&self) -> bool {
@@ -267,7 +272,9 @@ impl TakeRow for my::Row {
                 my::Value::Bytes(b) if column.character_set() == 63 => Value::bytes(b),
                 my::Value::Bytes(s) => Value::text(String::from_utf8(s)?),
                 my::Value::Int(i) if column.is_int64() => Value::int64(i),
+                my::Value::Int(i) if column.is_uint32() => Value::uint32(i as u32),
                 my::Value::Int(i) => Value::int32(i as i32),
+                my::Value::UInt(i) if column.is_uint32() => Value::uint32(u32::try_from(i)?),
                 my::Value::UInt(i) => Value::int64(i64::try_from(i).map_err(|_| {
                     let msg = "Unsigned integers larger than 9_223_372_036_854_775_807 are currently not handled.";
                     let kind = ErrorKind::value_out_of_range(msg);
@@ -315,6 +322,7 @@ impl TakeRow for my::Row {
                     t if t.is_enum() => Value::Enum(None),
                     t if t.is_null() => Value::Int32(None),
                     t if t.is_int64() => Value::Int64(None),
+                    t if t.is_uint32() => Value::UnsignedInt32(None),
                     t if t.is_int32() => Value::Int32(None),
                     t if t.is_float() => Value::Float(None),
                     t if t.is_double() => Value::Double(None),
diff --git a/src/connector/postgres/conversion.rs b/src/connector/postgres/conversion.rs
index ff935349..f4cd92d8 100644
--- a/src/connector/postgres/conversion.rs
+++ b/src/connector/postgres/conversion.rs
@@ -42,6 +42,7 @@ pub(crate) fn params_to_types(params: &[Value<'_>]) -> Vec<PostgresType> {
             match p {
                 Value::Int32(_) => PostgresType::INT4,
                 Value::Int64(_) => PostgresType::INT8,
+                Value::UnsignedInt32(_) => PostgresType::INT8,
                 Value::Float(_) => PostgresType::FLOAT4,
                 Value::Double(_) => PostgresType::FLOAT8,
                 Value::Text(_) => PostgresType::TEXT,
@@ -84,6 +85,7 @@ pub(crate) fn params_to_types(params: &[Value<'_>]) -> Vec<PostgresType> {
                     match first {
                         Value::Int32(_) => PostgresType::INT4_ARRAY,
                         Value::Int64(_) => PostgresType::INT8_ARRAY,
+                        Value::UnsignedInt32(_) => PostgresType::INT8_ARRAY,
                         Value::Float(_) => PostgresType::FLOAT4_ARRAY,
                         Value::Double(_) => PostgresType::FLOAT8_ARRAY,
                         Value::Text(_) => PostgresType::TEXT_ARRAY,
@@ -406,7 +408,7 @@ impl GetRow for PostgresRow {
                 PostgresType::OID_ARRAY => match row.try_get(i)? {
                     Some(val) => {
                         let val: Vec<Option<u32>> = val;
-                        let nums = val.into_iter().map(|oid| Value::Int64(oid.map(|oid| oid as i64)));
+                        let nums = val.into_iter().map(Value::UnsignedInt32);
 
                         Value::array(nums)
                     }
@@ -475,9 +477,9 @@ impl GetRow for PostgresRow {
                 PostgresType::OID => match row.try_get(i)? {
                     Some(val) => {
                         let val: u32 = val;
-                        Value::int64(val)
+                        Value::uint32(val)
                     }
-                    None => Value::Int64(None),
+                    None => Value::UnsignedInt32(None),
                 },
                 PostgresType::CHAR => match row.try_get(i)? {
                     Some(val) => {
@@ -680,6 +682,39 @@ impl<'a> ToSql for Value<'a> {
                     _ => None,
                 },
                 (Value::Int64(integer), &PostgresType::INT8) => integer.map(|integer| (integer as i64).to_sql(ty, out)),
+                (Value::UnsignedInt32(integer), &PostgresType::INT2) => match integer {
+                    Some(i) => {
+                        let integer = i16::try_from(*i).map_err(|_| {
+                            let kind = ErrorKind::conversion(format!(
+                                "Unable to fit unsigned integer value '{}' into an INT2 (16-bit signed integer).",
+                                i
+                            ));
+
+                            Error::builder(kind).build()
+                        })?;
+
+                        Some(integer.to_sql(ty, out))
+                    }
+                    None => None,
+                },
+                (Value::UnsignedInt32(integer), &PostgresType::INT4) => match integer {
+                    Some(i) => {
+                        let integer = i32::try_from(*i).map_err(|_| {
+                            let kind = ErrorKind::conversion(format!(
+                                "Unable to fit unsigned integer value '{}' into an INT2 (16-bit signed integer).",
+                                i
+                            ));
+
+                            Error::builder(kind).build()
+                        })?;
+
+                        Some(integer.to_sql(ty, out))
+                    }
+                    None => None,
+                },
+                (Value::UnsignedInt32(integer), &PostgresType::INT8) => {
+                    integer.map(|integer| (integer as i64).to_sql(ty, out))
+                }
                 #[cfg(feature = "bigdecimal")]
                 (Value::Int32(integer), &PostgresType::NUMERIC) => integer
                     .map(|integer| BigDecimal::from_i32(integer).unwrap())
@@ -728,6 +763,7 @@ impl<'a> ToSql for Value<'a> {
                 },
                 (Value::Int32(integer), _) => integer.map(|integer| integer.to_sql(ty, out)),
                 (Value::Int64(integer), _) => integer.map(|integer| integer.to_sql(ty, out)),
+                (Value::UnsignedInt32(integer), _) => integer.map(|integer| integer.to_sql(ty, out)),
                 (Value::Float(float), &PostgresType::FLOAT8) => float.map(|float| (float as f64).to_sql(ty, out)),
                 #[cfg(feature = "bigdecimal")]
                 (Value::Float(float), &PostgresType::NUMERIC) => float
diff --git a/src/connector/sqlite/conversion.rs b/src/connector/sqlite/conversion.rs
index 6d94b6b1..55767d61 100644
--- a/src/connector/sqlite/conversion.rs
+++ b/src/connector/sqlite/conversion.rs
@@ -76,6 +76,10 @@ impl TypeIdentifier for Column<'_> {
         )
     }
 
+    fn is_uint32(&self) -> bool {
+        false
+    }
+
     fn is_datetime(&self) -> bool {
         matches!(
             self.decl_type(),
@@ -253,6 +257,7 @@ impl<'a> ToSql for Value<'a> {
         let value = match self {
             Value::Int32(integer) => integer.map(ToSqlOutput::from),
             Value::Int64(integer) => integer.map(ToSqlOutput::from),
+            Value::UnsignedInt32(integer) => integer.map(|u| ToSqlOutput::from(u as i64)),
             Value::Float(float) => float.map(|f| f as f64).map(ToSqlOutput::from),
             Value::Double(double) => double.map(ToSqlOutput::from),
             Value::Text(cow) => cow.as_ref().map(|cow| ToSqlOutput::from(cow.as_ref())),
diff --git a/src/connector/type_identifier.rs b/src/connector/type_identifier.rs
index 9fcc46f6..ff5743e1 100644
--- a/src/connector/type_identifier.rs
+++ b/src/connector/type_identifier.rs
@@ -4,6 +4,7 @@ pub(crate) trait TypeIdentifier {
     fn is_double(&self) -> bool;
     fn is_int32(&self) -> bool;
     fn is_int64(&self) -> bool;
+    fn is_uint32(&self) -> bool;
     fn is_datetime(&self) -> bool;
     fn is_time(&self) -> bool;
     fn is_date(&self) -> bool;
diff --git a/src/serde.rs b/src/serde.rs
index 079f18fa..1881ac32 100644
--- a/src/serde.rs
+++ b/src/serde.rs
@@ -118,6 +118,8 @@ impl<'de> Deserializer<'de> for ValueDeserializer<'de> {
             Value::Int32(None) => visitor.visit_none(),
             Value::Int64(Some(i)) => visitor.visit_i64(i),
             Value::Int64(None) => visitor.visit_none(),
+            Value::UnsignedInt32(Some(i)) => visitor.visit_u32(i),
+            Value::UnsignedInt32(None) => visitor.visit_none(),
             Value::Boolean(Some(b)) => visitor.visit_bool(b),
             Value::Boolean(None) => visitor.visit_none(),
             Value::Char(Some(c)) => visitor.visit_char(c),
diff --git a/src/tests/types/mssql.rs b/src/tests/types/mssql.rs
index e90cef01..94ef3107 100644
--- a/src/tests/types/mssql.rs
+++ b/src/tests/types/mssql.rs
@@ -76,6 +76,14 @@ test_type!(bigint(
     Value::int64(i64::MAX),
 ));
 
+test_type!(bigint_from_u32(
+    mssql,
+    "bigint",
+    (Value::UnsignedInt32(None), Value::Int64(None)),
+    (Value::uint32(u32::MIN), Value::int64(u32::MIN as i64)),
+    (Value::uint32(u32::MAX), Value::int64(u32::MAX as i64)),
+));
+
 test_type!(float_24(mssql, "float(24)", Value::Float(None), Value::float(1.23456),));
 
 test_type!(real(mssql, "real", Value::Float(None), Value::float(1.123456)));
diff --git a/src/tests/types/mysql.rs b/src/tests/types/mysql.rs
index 97a920c9..d23cf7f4 100644
--- a/src/tests/types/mysql.rs
+++ b/src/tests/types/mysql.rs
@@ -65,9 +65,9 @@ test_type!(mediumint(
 test_type!(mediumint_unsigned(
     mysql,
     "mediumint unsigned",
-    Value::Int64(None),
-    Value::int64(0),
-    Value::int64(16777215)
+    Value::UnsignedInt32(None),
+    Value::uint32(0u32),
+    Value::uint32(16777215u32)
 ));
 
 test_type!(int(
@@ -81,18 +81,18 @@ test_type!(int(
 test_type!(int_unsigned(
     mysql,
     "int unsigned",
-    Value::Int64(None),
-    Value::int64(0),
-    Value::int64(2173158296i64),
-    Value::int64(4294967295i64)
+    Value::UnsignedInt32(None),
+    Value::uint32(0u32),
+    Value::uint32(2173158296u32),
+    Value::uint32(4294967295u32)
 ));
 
 test_type!(int_unsigned_not_null(
     mysql,
     "int unsigned not null",
-    Value::int64(0),
-    Value::int64(2173158296i64),
-    Value::int64(4294967295i64)
+    Value::uint32(0_u32),
+    Value::uint32(2173158296_u32),
+    Value::uint32(4294967295_u32)
 ));
 
 test_type!(bigint(
diff --git a/src/tests/types/postgres.rs b/src/tests/types/postgres.rs
index a098fa7a..c45cadd2 100644
--- a/src/tests/types/postgres.rs
+++ b/src/tests/types/postgres.rs
@@ -137,22 +137,28 @@ test_type!(float8_array(
     Value::array(vec![Value::double(1.1234), Value::double(4.321), Value::Double(None)])
 ));
 
-// NOTE: OIDs are unsigned 32-bit integers (see https://www.postgresql.org/docs/9.4/datatype-oid.html)
-// but a u32 cannot fit in an i32, so we always read OIDs back from the database as i64s.
 test_type!(oid_with_i32(
     postgresql,
     "oid",
-    (Value::Int32(None), Value::Int64(None)),
-    (Value::int32(i32::MAX), Value::int64(i32::MAX)),
-    (Value::int32(u32::MIN as i32), Value::int64(u32::MIN)),
+    (Value::Int32(None), Value::UnsignedInt32(None)),
+    (Value::int32(i32::MAX), Value::uint32(i32::MAX as u32)),
+    (Value::int32(u32::MIN as i32), Value::uint32(u32::MIN)),
+));
+
+test_type!(oid_with_u32(
+    postgresql,
+    "oid",
+    Value::UnsignedInt32(None),
+    Value::uint32(u32::MAX),
+    Value::uint32(u32::MIN),
 ));
 
 test_type!(oid_with_i64(
     postgresql,
     "oid",
-    Value::Int64(None),
-    Value::int64(u32::MAX),
-    Value::int64(u32::MIN),
+    (Value::Int64(None), Value::UnsignedInt32(None)),
+    (Value::int64(u32::MAX), Value::uint32(u32::MAX)),
+    (Value::int64(u32::MIN), Value::uint32(u32::MIN)),
 ));
 
 test_type!(oid_array(
@@ -160,10 +166,10 @@ test_type!(oid_array(
     "oid[]",
     Value::Array(None),
     Value::array(vec![
-        Value::int64(1),
-        Value::int64(2),
-        Value::int64(3),
-        Value::Int64(None)
+        Value::uint32(1_u32),
+        Value::uint32(2_u32),
+        Value::uint32(3_u32),
+        Value::UnsignedInt32(None)
     ]),
 ));
 
diff --git a/src/visitor/mssql.rs b/src/visitor/mssql.rs
index 19f65f29..0529e992 100644
--- a/src/visitor/mssql.rs
+++ b/src/visitor/mssql.rs
@@ -313,6 +313,7 @@ impl<'a> Visitor<'a> for Mssql<'a> {
         let res = match value {
             Value::Int32(i) => i.map(|i| self.write(i)),
             Value::Int64(i) => i.map(|i| self.write(i)),
+            Value::UnsignedInt32(i) => i.map(|i| self.write(i)),
             Value::Float(d) => d.map(|f| match f {
                 f if f.is_nan() => self.write("'NaN'"),
                 f if f == f32::INFINITY => self.write("'Infinity'"),
diff --git a/src/visitor/mysql.rs b/src/visitor/mysql.rs
index 493bc549..3b5f1c1c 100644
--- a/src/visitor/mysql.rs
+++ b/src/visitor/mysql.rs
@@ -125,6 +125,7 @@ impl<'a> Visitor<'a> for Mysql<'a> {
         let res = match value {
             Value::Int32(i) => i.map(|i| self.write(i)),
             Value::Int64(i) => i.map(|i| self.write(i)),
+            Value::UnsignedInt32(i) => i.map(|i| self.write(i)),
             Value::Float(d) => d.map(|f| match f {
                 f if f.is_nan() => self.write("'NaN'"),
                 f if f == f32::INFINITY => self.write("'Infinity'"),
diff --git a/src/visitor/postgres.rs b/src/visitor/postgres.rs
index 88a04a37..52cfe019 100644
--- a/src/visitor/postgres.rs
+++ b/src/visitor/postgres.rs
@@ -72,6 +72,7 @@ impl<'a> Visitor<'a> for Postgres<'a> {
         let res = match value {
             Value::Int32(i) => i.map(|i| self.write(i)),
             Value::Int64(i) => i.map(|i| self.write(i)),
+            Value::UnsignedInt32(i) => i.map(|i| self.write(i)),
             Value::Text(t) => t.map(|t| self.write(format!("'{}'", t))),
             Value::Enum(e) => e.map(|e| self.write(e)),
             Value::Bytes(b) => b.map(|b| self.write(format!("E'{}'", hex::encode(b)))),
diff --git a/src/visitor/sqlite.rs b/src/visitor/sqlite.rs
index 3783a826..dc221495 100644
--- a/src/visitor/sqlite.rs
+++ b/src/visitor/sqlite.rs
@@ -77,6 +77,7 @@ impl<'a> Visitor<'a> for Sqlite<'a> {
         let res = match value {
             Value::Int32(i) => i.map(|i| self.write(i)),
             Value::Int64(i) => i.map(|i| self.write(i)),
+            Value::UnsignedInt32(i) => i.map(|i| self.write(i)),
             Value::Text(t) => t.map(|t| self.write(format!("'{}'", t))),
             Value::Enum(e) => e.map(|e| self.write(e)),
             Value::Bytes(b) => b.map(|b| self.write(format!("x'{}'", hex::encode(b)))),