precision issues on MariaDB 10.2.x

[mia0x75]

Server is running MariaDB 10.2.11 w/ CentOS 7.x

Table schemas:

CREATE TABLE `dt_decimal_1` (
  `c` decimal(38,0) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

CREATE TABLE `dt_decimal_2` (
  `c` decimal(38,19) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

CREATE TABLE `dt_decimal_3` (
  `c` decimal(38,38) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4

insert data

INSERT INTO dt_decimal_1 VALUES (99999999999999999999999999999999999999);
INSERT INTO dt_decimal_2 VALUES (9999999999999999999.9999999999999999999);
INSERT INTO dt_decimal_3 VALUES (0.99999999999999999999999999999999999999);

go-canal output:

================================================================================
Table:          drafts.dt_decimal_1
Action:         insert
Rows:           [[1e+38]]
================================================================================
Table:          drafts.dt_decimal_2
Action:         insert
Rows:           [[1e+19]]
================================================================================
Table:          drafts.dt_decimal_3
Action:         insert
Rows:           [[1]]

[siddontang]

I use float64 to save the decimal value, this may lose the precision, but I have no time to improve it. Maybe it is better to find a good decimal implementation to fully support this.