diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index 2f0bf35e34626b1d3c661328ddd4f01584e7ac9a..0baf6261f08689bc2250843c87f4b302be69d3a5 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -1789,7 +1789,7 @@ int32_t validateOneColumn(SSqlCmd* pCmd, TAOS_FIELD* pColField) {
 
   // field name must be unique
   for (int32_t i = 0; i < numOfTags + numOfCols; ++i) {
-    if (strncasecmp(pColField->name, pSchema[i].name, sizeof(pColField->name) - 1) == 0) {
+    if (strncmp(pColField->name, pSchema[i].name, sizeof(pColField->name) - 1) == 0) {
       //return tscErrorMsgWithCode(TSDB_CODE_TSC_DUP_COL_NAMES, tscGetErrorMsgPayload(pCmd), pColField->name, NULL);
       return invalidOperationMsg(tscGetErrorMsgPayload(pCmd), "duplicated column names");
     }
@@ -1803,7 +1803,7 @@ static bool has(SArray* pFieldList, int32_t startIdx, const char* name) {
   size_t numOfCols = taosArrayGetSize(pFieldList);
   for (int32_t j = startIdx; j < numOfCols; ++j) {
     TAOS_FIELD* field = taosArrayGet(pFieldList, j);
-    if (strncasecmp(name, field->name, sizeof(field->name) - 1) == 0) return true;
+    if (strncmp(name, field->name, sizeof(field->name) - 1) == 0) return true;
   }
 
   return false;
@@ -3448,7 +3448,7 @@ static int16_t doGetColumnIndex(SQueryInfo* pQueryInfo, int32_t index, SStrToken
       continue;
     }
 
-    if (strncasecmp(pSchema[i].name, pToken->z, pToken->n) == 0) {
+    if (strncmp(pSchema[i].name, pToken->z, pToken->n) == 0) {
       columnIndex = i;
       break;
     }
@@ -3468,7 +3468,7 @@ int32_t doGetColumnIndexByName(SStrToken* pToken, SQueryInfo* pQueryInfo, SColum
   if (isTablenameToken(pToken)) {
     pIndex->columnIndex = TSDB_TBNAME_COLUMN_INDEX;
   } else if (strlen(DEFAULT_PRIMARY_TIMESTAMP_COL_NAME) == pToken->n &&
-            strncasecmp(pToken->z, DEFAULT_PRIMARY_TIMESTAMP_COL_NAME, pToken->n) == 0) {
+            strncmp(pToken->z, DEFAULT_PRIMARY_TIMESTAMP_COL_NAME, pToken->n) == 0) {
     pIndex->columnIndex = PRIMARYKEY_TIMESTAMP_COL_INDEX; // just make runtime happy, need fix java test case InsertSpecialCharacterJniTest
   } else {
     // not specify the table name, try to locate the table index by column name
diff --git a/src/common/src/tname.c b/src/common/src/tname.c
index 68aa1be6b2ed0d9d1a248e6fc6ee2e701071fb21..62af3385f355cc4cbed2e9f4120dff431e47c92f 100644
--- a/src/common/src/tname.c
+++ b/src/common/src/tname.c
@@ -277,7 +277,7 @@ static bool doValidateSchema(SSchema* pSchema, int32_t numOfCols, int32_t maxLen
 
     // 3. valid column names
     for (int32_t j = i + 1; j < numOfCols; ++j) {
-      if (strncasecmp(pSchema[i].name, pSchema[j].name, sizeof(pSchema[i].name) - 1) == 0) {
+      if (strncmp(pSchema[i].name, pSchema[j].name, sizeof(pSchema[i].name) - 1) == 0) {
         return false;
       }
     }
diff --git a/src/mnode/src/mnodeTable.c b/src/mnode/src/mnodeTable.c
index 875ed846ee694b91706a72238a1838e8232be147..116c1f41d7c240e266db7c0d93168c8e3ddc6d15 100644
--- a/src/mnode/src/mnodeTable.c
+++ b/src/mnode/src/mnodeTable.c
@@ -2352,7 +2352,7 @@ static int32_t mnodeProcessDropChildTableMsg(SMnodeMsg *pMsg) {
 static int32_t mnodeFindNormalTableColumnIndex(SCTableObj *pTable, char *colName) {
   SSchema *schema = (SSchema *) pTable->schema;
   for (int32_t col = 0; col < pTable->numOfColumns; col++) {
-    if (strcasecmp(schema[col].name, colName) == 0) {
+    if (strcmp(schema[col].name, colName) == 0) {
       return col;
     }
   }
diff --git a/tests/develop-test/0-others/TD-12435.py b/tests/develop-test/0-others/TD-12435.py
index 33d44dab2832804c5d1cc9c24dcf0b58b0d03614..4d6df436c89dc9e8903fc3677401f21b4762ffaf 100644
--- a/tests/develop-test/0-others/TD-12435.py
+++ b/tests/develop-test/0-others/TD-12435.py
@@ -34,7 +34,7 @@ class TDTestCase:
         tdSql.prepare()
 
         print("============== STEP 1 ===== prepare data & validate json string")
-        tdSql.execute("create table if not exists st(ts timestamp, dataInt int)")
+        tdSql.execute("create table if not exists st(ts timestamp, `dataInt` int)")
         tdSql.execute("create table st_from_sub as select avg(`dataInt`) from st interval(1m)")
         tdSql.query("describe st_from_sub")
         tdSql.checkData(1, 0, 'avg__dataInt__')
@@ -45,4 +45,4 @@ class TDTestCase:
 
 
 tdCases.addWindows(__file__, TDTestCase())
-tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file
+tdCases.addLinux(__file__, TDTestCase())