达梦数据库作为writer时，支不支持更新

达梦数据库作为writer时， writwMode能不能设置为update；目前我的是如下：
`{
"job": {
"setting": {
"speed": {
"channel":"4"
}
},
"content": [
{
"reader": {
"name": "mysqlreader",
"parameter": {
"username": "root",
"password": "root",
"connection": [
{
"querySql": [
"SELECT id,name FROM user"
],
"jdbcUrl": ["jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&zeroDateTimeBehavior=round"]
}
]
}
},
"writer": {
"name": "rdbmswriter",
"parameter": {
"writeMode":"replace",
"column": [
"id",
"name"
],
"connection": [
{
"jdbcUrl": "jdbc:dm://127.0.0.1:5236/TEST",
"table": ["TEMP_USER"]
}
],
"username": "TEST",
"password": "123456789",
"postSql": [],
"preSql": []
}
}
}
]
}
}`
执行时提示我：Code:[DBUtilErrorCode-00], Description:[您的配置错误.]. - 写入模式(writeMode)配置有误. 因为不支持配置参数项 writeMode: replace, 仅使用insert sql 插入数据. 请检查您的配置并作出修改.

Start by tracing the rdbmswriter handling of the writeMode value shown in the configuration and the validation error reported for Dameng. Determine whether update mode is intended to be supported, then document the required behavior and verify it with a representative Dameng writer test; done means valid update configuration is accepted and performs the expected writes.

Written by the indexing model from the issue text.