断开dplyr中的src_tbls连接 [英] Disconnecting src_tbls connection in dplyr

问题描述

是否有一种方法可以强制断开 dplyr 中的 src_tbls 对象，类似于 RPostgreSQL :: dbDisconnect ？

Is there a way to force disconnection of a src_tbls object in dplyr similar to RPostgreSQL::dbDisconnect?

例如参见

> src_temp <- src_postgres(dbname = "temp", host = "127.0.0.1", port = 5432, user = "x", password = "y")
Error in postgresqlNewConnection(drv, ...) : 
  RS-DBI driver: (cannot allocate a new connection -- maximum of 16 connections already opened)

作为旁注，它会在几秒钟后很快自动断开连接：

As a side note, it does auto-disconnect quite quickly after a few seconds:

Auto-disconnecting postgres connection (3734, 26)

之后，您可以运行 src_postgres 命令。

after which you can run the src_postgres command again.

推荐答案

您可以执行以下操作：

RPostgreSQL::dbDisconnect(src_temp$con)

断开连接。

这就是通过 dplyr （通过 dbi- s3.r 源文件）：

That's what's called on garbage collection from this function in dplyr (via the dbi-s3.r source file):

# Creates an environment that disconnects the database when it's
# garbage collected
db_disconnector <- function(con, name, quiet = FALSE) {
  reg.finalizer(environment(), function(...) {
    if (!quiet) {
      message("Auto-disconnecting ", name, " connection ",
        "(", paste(con@Id, collapse = ", "), ")")
    }
    dbDisconnect(con)
  })
  environment()
}

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