[TD-10700]<enhance>: The escape char backstick can be used for both tag name and column name

src/client/inc/tscParseLine.h

@@ -24,7 +24,6 @@ extern "C" {
 #define SML_TIMESTAMP_MILLI_SECOND_DIGITS 13
 
 typedef TSDB_SML_PROTOCOL_TYPE SMLProtocolType;
-#define SML_ESCAPE_CHAR_SIZE 2
 
 typedef struct {
   char* key;

src/client/src/tscParseLineProtocol.c

@@ -1925,7 +1925,7 @@ static int32_t parseSmlKey(TAOS_SML_KV *pKV, const char **index, SHashObj *pHash
     return TSDB_CODE_TSC_LINE_SYNTAX_ERROR;
   }
 
-  pKV->key = calloc(len + SML_ESCAPE_CHAR_SIZE + 1, 1);
+  pKV->key = calloc(len + TS_ESCAPE_CHAR_SIZE + 1, 1);
   memcpy(pKV->key, key, len + 1);
   addEscapeCharToString(pKV->key, len);
   tscDebug("SML:0x%"PRIx64" Key:%s|len:%d", info->id, pKV->key, len);
@@ -2022,7 +2022,7 @@ static int32_t parseSmlMeasurement(TAOS_SML_DATA_POINT *pSml, const char **index
   const char *cur = *index;
   int16_t len = 0;
 
-  pSml->stableName = calloc(TSDB_TABLE_NAME_LEN + SML_ESCAPE_CHAR_SIZE, 1);
+  pSml->stableName = calloc(TSDB_TABLE_NAME_LEN + TS_ESCAPE_CHAR_SIZE, 1);
   if (pSml->stableName == NULL){
       return TSDB_CODE_TSC_OUT_OF_MEMORY;
   }
@@ -2119,7 +2119,7 @@ static int32_t parseSmlKvPairs(TAOS_SML_KV **pKVs, int *num_kvs,
       goto error;
     }
     if (!isField && (strcasecmp(pkv->key, "`ID`") == 0)) {
-      smlData->childTableName = malloc(pkv->length + SML_ESCAPE_CHAR_SIZE + 1);
+      smlData->childTableName = malloc(pkv->length + TS_ESCAPE_CHAR_SIZE + 1);
       memcpy(smlData->childTableName, pkv->value, pkv->length);
       strntolower_s(smlData->childTableName, smlData->childTableName, (int32_t)pkv->length);
       addEscapeCharToString(smlData->childTableName, (int32_t)pkv->length);

src/client/src/tscSQLParser.c

@@ -6324,8 +6324,8 @@ int32_t setAlterTableInfo(SSqlObj* pSql, struct SSqlInfo* pInfo) {
     //handle Escape character backstick
     if (name.z[0] == TS_ESCAPE_CHAR && name.z[name.n - 1] == TS_ESCAPE_CHAR) {
       memmove(name.z, name.z + 1, name.n);
-      name.z[name.n - 2] = '\0';
-      name.n -= 2;
+      name.z[name.n - TS_ESCAPE_CHAR_SIZE] = '\0';
+      name.n -= TS_ESCAPE_CHAR_SIZE;
     }
 
     if (getColumnIndexByName(&name, pQueryInfo, &columnIndex, tscGetErrorMsgPayload(pCmd)) != TSDB_CODE_SUCCESS) {

src/inc/taosdef.h

@@ -99,6 +99,7 @@ extern const int32_t TYPE_BYTES[15];
 
 #define TS_PATH_DELIMITER "."
 #define TS_ESCAPE_CHAR '`'
+#define TS_ESCAPE_CHAR_SIZE 2
 
 #define TSDB_TIME_PRECISION_MILLI 0
 #define TSDB_TIME_PRECISION_MICRO 1