使用ROracle dbWriteTable将POSIXct写回Oracle DB

Question

在Oracle DB中:

DESCRIBE ORACLE_DB_TABLE;

|---------------------------------------|
| Column Name      | Data Type          |
|---------------------------------------|
| TRANSACTION_TIME | DATE               |
| TRANSACTION_ID   | VARCHAR2 (20 Byte) |
| TRANSACTION_AMT  | NUMBER (38,10)]    |
|---------------------------------------|

在R:

> r_data_table
      TRANSACTION_TIME TRANSACTION_ID TRANSACTION_AMT
1: 2015-04-28 11:12:24            ABC             123
> dbWriteTable(conn, "ORACLE_DB_TABLE", r_data_table, overwrite = F, append = T, row.names = F)
> Error in .oci.WriteTable(conn, name, value, row.names = row.names, overwrite = overwrite,  :
  Error in .oci.ValidateZoneInEnv(FALSE) :
  environment variable 'ORA_SDTZ()' must be set to the same time zone region as the the environment variable 'TZ(Europe/London)'
> dbGetQuery(conn, "SELECT SESSIONTIMEZONE FROM DUAL")
  SESSIONTIMEZONE
1   Europe/London

从错误消息中可以看出,我已将环境变量TZ设置为R ="Europe/London".此外,从上面的查询中,您可以看到Oracle中的会话时区也是"欧洲/伦敦".

为什么错误消息抱怨Oracle和R之间的时区不同？

如何将R中的POSIXct写入Oracle DB中的DATE列？

Answer 1

以下作品:

> Sys.setenv(TZ = "GMT")
> Sys.setenv(ORA_SDTZ = "GMT")
> dbWriteTable(conn, "ORACLE_DB_TABLE", r_data_table, overwrite = F, append = T, row.names = F)