DB::Exception: Wrong precision:128

[fzhedu]

create table t (c_create_time varchar(128));
alter table t set tiflash replica 1;
set @@tidb_isolation_read_engines='tiflash,tidb'; set @@tidb_allow_mpp=1; set @@tidb_enforce_mpp=1;

mysql> SELECT FROM_UNIXTIME(c_create_time,'%Y-%m-%d')  FROM t;
ERROR 1105 (HY000): DB::Exception: Wrong precision:128

mysql> desc SELECT FROM_UNIXTIME(c_create_time,'%Y-%m-%d')  FROM t;
+---------------------------+----------+--------------+---------------+--------------------------------------------------------------------------------------+
| id                        | estRows  | task         | access object | operator info                                                                        |
+---------------------------+----------+--------------+---------------+--------------------------------------------------------------------------------------+
| TableReader_9             | 10000.00 | root         |               | data:ExchangeSender_8                                                                |
| └─ExchangeSender_8        | 10000.00 | cop[tiflash] |               | ExchangeType: PassThrough                                                            |
|   └─Projection_4          | 10000.00 | cop[tiflash] |               | from_unixtime(cast(test.t.c_create_time, decimal(128,0) BINARY), %Y-%m-%d)->Column#3 |
|     └─TableFullScan_7     | 10000.00 | cop[tiflash] | table:t       | keep order:false, stats:pseudo                                                       |
+---------------------------+----------+--------------+---------------+--------------------------------------------------------------------------------------+
4 rows in set (0.00 sec)