[Feature] support bit_length function

be/src/exprs/string_functions.cpp

@@ -1007,4 +1007,14 @@ StringVal StringFunctions::replace(FunctionContext* context, const StringVal& or
     }
     return AnyValUtil::from_string_temp(context, orig_str);
 }
+// Implementation of BIT_LENGTH
+//   int bit_length(string input)
+// Returns the length in bits of input. If input == NULL, returns
+// NULL per MySQL
+IntVal StringFunctions::bit_length(FunctionContext* context, const StringVal& str) {
+    if (str.is_null) {
+        return IntVal::null();
+    }
+    return IntVal(str.len * 8);
+}
 } // namespace doris

be/src/exprs/string_functions.h

@@ -180,6 +180,9 @@ class StringFunctions {
 
     static StringVal replace(FunctionContext* context, const StringVal& origStr,
                              const StringVal& oldStr, const StringVal& newStr);
+
+    static doris_udf::IntVal bit_length(doris_udf::FunctionContext* context,
+                                    const doris_udf::StringVal& str);
 };
 } // namespace doris
 

be/test/exprs/string_functions_test.cpp

@@ -630,6 +630,20 @@ TEST_F(StringFunctionsTest, parse_url) {
                                          StringVal("port")));
 }
 
+TEST_F(StringFunctionsTest, bit_length) {
+    doris_udf::FunctionContext* context = new doris_udf::FunctionContext();
+
+    ASSERT_EQ(IntVal(40), StringFunctions::bit_length(context, StringVal("hello")));
+
+    ASSERT_EQ(IntVal::null(), StringFunctions::bit_length(context, StringVal::null()));
+
+    ASSERT_EQ(IntVal(0), StringFunctions::bit_length(context, StringVal("")));
+
+    ASSERT_EQ(IntVal(88), StringFunctions::bit_length(context, StringVal("hello你好")));
+
+    delete context;
+}
+
 } // namespace doris
 
 int main(int argc, char** argv) {

docs/.vuepress/sidebar/en.js

@@ -294,6 +294,7 @@ module.exports = [
             children: [
               "append_trailing_char_if_absent",
               "ascii",
+              "bit_length",
               "char_length",
               "concat",
               "concat_ws",

docs/.vuepress/sidebar/zh-CN.js

@@ -299,6 +299,7 @@ module.exports = [
             children: [
               "append_trailing_char_if_absent",
               "ascii",
+              "bit_length",
               "char_length",
               "concat",
               "concat_ws",

docs/en/sql-reference/sql-functions/string-functions/bit_length.md

@@ -0,0 +1,54 @@
+---
+{
+    "title": "bit_length",
+    "language": "en"
+}
+---
+
+<!-- 
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you 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.
+-->
+
+# bit_length
+## Description
+### Syntax
+
+'INT bit_length (VARCHAR str)'
+
+
+Return length of argument in bits。
+
+## example
+
+```
+mysql> select bit_length("abc");
++-------------------+
+| bit_length('abc') |
++-------------------+
+|                24 |
++-------------------+
+
+mysql> select bit_length("中国");
++----------------------+
+| bit_length('中国')    |
++----------------------+
+|                   48 |
++----------------------+
+```
+## keyword
+BIT_LENGTH

docs/zh-CN/sql-reference/sql-functions/string-functions/bit_length.md

@@ -0,0 +1,54 @@
+---
+{
+    "title": "bit_length",
+    "language": "zh-CN"
+}
+---
+
+<!-- 
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you 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.
+-->
+
+# bit_length
+## description
+### Syntax
+
+`INT bit_length(VARCHAR str)`
+
+
+返回字符串的位长度。
+
+## example
+
+```
+mysql> select bit_length("abc");
++-------------------+
+| bit_length('abc') |
++-------------------+
+|                24 |
++-------------------+
+
+mysql> select bit_length("中国");
++----------------------+
+| bit_length('中国')    |
++----------------------+
+|                   48 |
++----------------------+
+```
+## keyword
+BIT_LENGTH

gensrc/script/doris_builtins_functions.py

@@ -696,6 +696,8 @@
 	'_ZN5doris15StringFunctions30append_trailing_char_if_absentEPN9doris_udf15FunctionContextERKNS1_9StringValES6_'],
     [['length'], 'INT', ['VARCHAR'],
             '_ZN5doris15StringFunctions6lengthEPN9doris_udf15FunctionContextERKNS1_9StringValE'],
+    [['bit_length'], 'INT', ['VARCHAR'],
+            '_ZN5doris15StringFunctions10bit_lengthEPN9doris_udf15FunctionContextERKNS1_9StringValE'],
     [['char_length', 'character_length'], 'INT', ['VARCHAR'],
             '_ZN5doris15StringFunctions16char_utf8_lengthEPN9doris_udf15FunctionContextERKNS1_9StringValE'],
    [['lower', 'lcase'], 'VARCHAR', ['VARCHAR'],