diff --git a/be/src/vec/common/string_ref.h b/be/src/vec/common/string_ref.h
index 587924b45e31a7..72a7a911210f95 100644
--- a/be/src/vec/common/string_ref.h
+++ b/be/src/vec/common/string_ref.h
@@ -22,10 +22,10 @@
 
 // IWYU pragma: no_include <crc32intrin.h>
 #include <glog/logging.h>
-#include <stdint.h>
 
 #include <algorithm>
 #include <climits>
+#include <cstdint>
 #include <cstring>
 #include <ostream>
 #include <string>
@@ -38,7 +38,6 @@
 #include "util/hash_util.hpp"
 #include "util/slice.h"
 #include "util/sse_util.hpp"
-#include "vec/common/string_ref.h"
 #include "vec/common/unaligned.h"
 #include "vec/core/types.h"
 
@@ -150,7 +149,8 @@ inline bool memequalSSE2Wide(const char* p1, const char* p2, size_t size) {
 //   - s1/n1: ptr/len for the first string
 //   - s2/n2: ptr/len for the second string
 //   - len: min(n1, n2) - this can be more cheaply passed in by the caller
-inline int string_compare(const char* s1, int64_t n1, const char* s2, int64_t n2, int64_t len) {
+PURE inline int string_compare(const char* s1, int64_t n1, const char* s2, int64_t n2,
+                               int64_t len) {
     DCHECK_EQ(len, std::min(n1, n2));
 #if defined(__SSE4_2__) || defined(__aarch64__)
     while (len >= sse_util::CHARS_PER_128_BIT_REGISTER) {
@@ -199,8 +199,8 @@ struct StringRef {
 
     std::string to_string() const { return std::string(data, size); }
     std::string debug_string() const { return to_string(); }
-    std::string_view to_string_view() const { return std::string_view(data, size); }
-    Slice to_slice() const { return doris::Slice(data, size); }
+    std::string_view to_string_view() const { return {data, size}; }
+    Slice to_slice() const { return {data, size}; }
 
     // this is just for show, e.g. print data to error log, to avoid print large string.
     std::string to_prefix(size_t length) const { return std::string(data, std::min(length, size)); }
@@ -209,7 +209,7 @@ struct StringRef {
     operator std::string_view() const { return std::string_view {data, size}; }
 
     StringRef substring(int start_pos, int new_len) const {
-        return StringRef(data + start_pos, (new_len < 0) ? (size - start_pos) : new_len);
+        return {data + start_pos, (new_len < 0) ? (size - start_pos) : new_len};
     }
 
     StringRef substring(int start_pos) const { return substring(start_pos, size - start_pos); }
@@ -255,7 +255,9 @@ struct StringRef {
             }
         }
 
-        return string_compare(this->data, this->size, other.data, other.size, l);
+        // string_compare doesn't have sign result
+        int cmp_result = string_compare(this->data, this->size, other.data, other.size, l);
+        return (cmp_result > 0) - (cmp_result < 0);
     }
 
     void replace(const char* ptr, int len) {
@@ -363,8 +365,8 @@ inline size_t hash_less_than8(const char* data, size_t size) {
 
 inline size_t hash_less_than16(const char* data, size_t size) {
     if (size > 8) {
-        doris::vectorized::UInt64 a = unaligned_load<doris::vectorized::UInt64>(data);
-        doris::vectorized::UInt64 b = unaligned_load<doris::vectorized::UInt64>(data + size - 8);
+        auto a = unaligned_load<doris::vectorized::UInt64>(data);
+        auto b = unaligned_load<doris::vectorized::UInt64>(data + size - 8);
         return hash_len16(a, rotate_by_at_least1(b + size, size)) ^ b;
     }
 
@@ -388,13 +390,13 @@ struct CRC32Hash {
         size_t res = -1ULL;
 
         do {
-            doris::vectorized::UInt64 word = unaligned_load<doris::vectorized::UInt64>(pos);
+            auto word = unaligned_load<doris::vectorized::UInt64>(pos);
             res = _mm_crc32_u64(res, word);
 
             pos += 8;
         } while (pos + 8 < end);
 
-        doris::vectorized::UInt64 word = unaligned_load<doris::vectorized::UInt64>(
+        auto word = unaligned_load<doris::vectorized::UInt64>(
                 end - 8); /// I'm not sure if this is normal.
         res = _mm_crc32_u64(res, word);
 
diff --git a/regression-test/data/query_p0/sql_functions/string_functions/test_string_function.out b/regression-test/data/query_p0/sql_functions/string_functions/test_string_function.out
index e3ca494c632fb9..69ce99277fa878 100644
Binary files a/regression-test/data/query_p0/sql_functions/string_functions/test_string_function.out and b/regression-test/data/query_p0/sql_functions/string_functions/test_string_function.out differ
diff --git a/regression-test/suites/query_p0/sql_functions/string_functions/test_string_function.groovy b/regression-test/suites/query_p0/sql_functions/string_functions/test_string_function.groovy
index 64798978d3b94b..f8fe485f96732e 100644
--- a/regression-test/suites/query_p0/sql_functions/string_functions/test_string_function.groovy
+++ b/regression-test/suites/query_p0/sql_functions/string_functions/test_string_function.groovy
@@ -358,4 +358,7 @@ suite("test_string_function", "arrow_flight_sql") {
     qt_sql_func_char9 """ select char(0) = ' '; """
     qt_sql_func_char10 """ select char(0) = '\0'; """
 
+    qt_strcmp1 """ select strcmp('a', 'abc'); """
+    qt_strcmp2 """ select strcmp('abc', 'abc'); """
+    qt_strcmp3 """ select strcmp('abcd', 'abc'); """
 }