From fb36f5e24e4857b3d97d14b1a888e78ae4b9ab00 Mon Sep 17 00:00:00 2001
From: Haojun Liao <hjliao@taosdata.com>
Date: Fri, 1 Apr 2022 19:10:53 +0800
Subject: [PATCH] [td-14428] return correct length for both nchar and varchar
 type.

---
 source/client/inc/clientInt.h  |  1 +
 source/client/src/clientEnv.c  |  1 +
 source/client/src/clientImpl.c | 16 ++++++++++++++--
 source/client/src/clientMain.c |  2 +-
 4 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/source/client/inc/clientInt.h b/source/client/inc/clientInt.h
index 49cb12cccd..e930dc2675 100644
--- a/source/client/inc/clientInt.h
+++ b/source/client/inc/clientInt.h
@@ -153,6 +153,7 @@ typedef struct SReqResultInfo {
   const char*    pRspMsg;
   const char*    pData;
   TAOS_FIELD*    fields;
+  TAOS_FIELD*    userFields; // the fields info that return to user
   uint32_t       numOfCols;
   int32_t*       length;
   char**         convertBuf;
diff --git a/source/client/src/clientEnv.c b/source/client/src/clientEnv.c
index 53cc77af1a..769870ada8 100644
--- a/source/client/src/clientEnv.c
+++ b/source/client/src/clientEnv.c
@@ -169,6 +169,7 @@ static void doFreeReqResultInfo(SReqResultInfo *pResInfo) {
   taosMemoryFreeClear(pResInfo->row);
   taosMemoryFreeClear(pResInfo->pCol);
   taosMemoryFreeClear(pResInfo->fields);
+  taosMemoryFreeClear(pResInfo->userFields);
 
   if (pResInfo->convertBuf != NULL) {
     for (int32_t i = 0; i < pResInfo->numOfCols; ++i) {
diff --git a/source/client/src/clientImpl.c b/source/client/src/clientImpl.c
index 8cd53f18b0..4b41785d08 100644
--- a/source/client/src/clientImpl.c
+++ b/source/client/src/clientImpl.c
@@ -228,12 +228,24 @@ void setResSchemaInfo(SReqResultInfo* pResInfo, const SSchema* pSchema, int32_t
   assert(pSchema != NULL && numOfCols > 0);
 
   pResInfo->numOfCols = numOfCols;
-  pResInfo->fields = taosMemoryCalloc(numOfCols, sizeof(pSchema[0]));
+  pResInfo->fields = taosMemoryCalloc(numOfCols, sizeof(TAOS_FIELD));
+  pResInfo->userFields = taosMemoryCalloc(numOfCols, sizeof(TAOS_FIELD));
 
   for (int32_t i = 0; i < pResInfo->numOfCols; ++i) {
     pResInfo->fields[i].bytes = pSchema[i].bytes;
-    pResInfo->fields[i].type = pSchema[i].type;
+    pResInfo->fields[i].type  = pSchema[i].type;
+
+    pResInfo->userFields[i].bytes = pSchema[i].bytes;
+    pResInfo->userFields[i].type  = pSchema[i].type;
+
+    if (pSchema[i].type == TSDB_DATA_TYPE_VARCHAR) {
+      pResInfo->userFields[i].bytes -= VARSTR_HEADER_SIZE;
+    } else if (pSchema[i].type == TSDB_DATA_TYPE_NCHAR) {
+      pResInfo->userFields[i].bytes = (pResInfo->userFields[i].bytes - VARSTR_HEADER_SIZE) / TSDB_NCHAR_SIZE;
+    }
+
     tstrncpy(pResInfo->fields[i].name, pSchema[i].name, tListLen(pResInfo->fields[i].name));
+    tstrncpy(pResInfo->userFields[i].name, pSchema[i].name, tListLen(pResInfo->userFields[i].name));
   }
 }
 
diff --git a/source/client/src/clientMain.c b/source/client/src/clientMain.c
index 42d4b5b2e5..2dd77b7f22 100644
--- a/source/client/src/clientMain.c
+++ b/source/client/src/clientMain.c
@@ -146,7 +146,7 @@ TAOS_FIELD *taos_fetch_fields(TAOS_RES *res) {
   }
 
   SReqResultInfo *pResInfo = &(((SRequestObj *)res)->body.resInfo);
-  return pResInfo->fields;
+  return pResInfo->userFields;
 }
 
 TAOS_RES *taos_query(TAOS *taos, const char *sql) {