TD-1450 change maxSqlLength from 8M to 1M

src/inc/taosdef.h

@@ -244,7 +244,7 @@ void tsDataSwap(void *pLeft, void *pRight, int32_t type, int32_t size, void* buf
 #define TSDB_MAX_SAVED_SQL_LEN    TSDB_MAX_COLUMNS * 64
 #define TSDB_MAX_SQL_LEN          TSDB_PAYLOAD_SIZE
 #define TSDB_MAX_SQL_SHOW_LEN     256
-#define TSDB_MAX_ALLOWED_SQL_LEN  (8*1024*1024U)          // sql length should be less than 8mb
+#define TSDB_MAX_ALLOWED_SQL_LEN  (1*1024*1024U)          // sql length should be less than 8mb
 
 #define TSDB_MAX_BYTES_PER_ROW    16384
 #define TSDB_MAX_TAGS_LEN         16384