Postgres DB不能与RJDBC连接到R

I've been trying to query data from a PostgreSQL DB via R. I've tried skinning the cat with a few different packages (RODBC, RJDBC, DBI, RPostgres, etc), but I seem to keep getting driver errors. Oddly, I never have trouble using the same drivers/URL's and settings to connect to Postgres from SQLWorkbench/J.

我一直试图通过r从PostgreSQL DB查询数据，我尝试过用一些不同的包(RODBC、RJDBC、DBI、RPostgres等)剥猫皮，但我似乎一直在得到驱动程序错误。奇怪的是，我从来没有遇到过使用相同的驱动/URL和设置从SQLWorkbench/J连接到Postgres的问题。

I've tried using postgresql-9.2-1002.jdbc4.jar and postgresql-9.3-1100.jdbc41.jar, as well as the generic "PostgreSQL" driver in R. The two jar files are the (i) the driver I use all the time with SQLWorkbench/J and (ii) the slightly newer version of that same driver, respectively. Yet, when I try to use it...

我试着使用postgresql - 9.2 - 1002. - jdbc4。jar和postgresql - 9.3 - 1100. - jdbc41。jar和r中的通用的“PostgreSQL”驱动程序一样，这两个jar文件分别是(i)我一直使用的SQLWorkbench/J驱动程序和(ii)相同驱动程序的稍微更新的版本。然而，当我尝试使用它的时候……

drv_custom <- JDBC(driverClass = "org.postgresql.Driver", classPath="/Users/xxxx/postgresql-9.3-1100.jdbc41.jar")

I get an error:

我得到一个错误:

Error in .jfindClass(as.character(driverClass)[1]) : class not found

OK, so next I try it with the generic driver:

好的，接下来我要用通用驱动程序来尝试

drv_generic <- dbDriver("PostgreSQL")

and strangely, it doesn't want me to enter a username:

奇怪的是，它不希望我输入用户名:

>con <- dbConnect(drv=drv_generic, "jdbc:postgresql://xxx.xxxxx.com", port=xxxx,     uid="xxxx", password="xxxx")
>Error in postgresqlNewConnection(drv, ...) : unused argument (uid = "xxxx")

so I try it without user/uid:

所以我尝试了没有用户/uid:

con <- dbConnect(drv_generic, "jdbc:postgresql://padb-01.jiwiredev.com:5439", password="paraccel")

con <- dbConnect(drv_generic， "jdbc:postgresql://padb-01.jiwiredev.com:5439"， password="paraccel")

and get an error....

和得到一个错误....

Error in postgresqlNewConnection(drv, ...) : 
RS-DBI driver: (could not connect jdbc:postgresql://padb-01.xxx.com:5439@local on dbname "jdbc:postgresql://xxxx.xxxx.com:5439")

Apparently the syntax is wrong?

语法显然是错误的?

Then I circle back to trying the "custom" driver (either one of the .jar files from earlier) but without the driverClass specified.

然后，我返回到尝试“自定义”驱动程序(前面的一个.jar文件)，但是没有指定驱动程序类。

drv_custom1 <- JDBC( classPath="/Users/xxxx/postgresql-9.2-1002.jdbc4.jar")

drv_custom1 < - JDBC(classPath = " /用户/ xxxx / postgresql - 9.2 - 1002. - jdbc4.jar”)

con <- dbConnect(drv=drv_custom1, "jdbc:postgresql://xxx.xxx.com", port=5439, uid="paraccel", pwd="paraccel")

con <- dbConnect(drv=drv_custom1， "jdbc:postgresql://xxx.xxx.com"， port=5439, uid="paraccel"， pwd="paraccel")

and get this error:

并得到这个错误:

Error in .jcall(drv@jdrv, "Ljava/sql/Connection;", "connect", as.character(url)[1],  : 
RcallMethod: attempt to call a method of a NULL object.

I tried it again with a slight alteration to the syntax:

我又试了一次，稍微改动了一下语法:

con <- dbConnect(drv=drv_custom1, url="jdbc:postgresql://xxxx.xxxx.com", port=xxxx, uid="xxxx", pwd="xxxxx",dsn="xxxx")

and got the same error. I tried a number of other variations/approaches as well. I think part of my confusion comes from the fact that the documentation is handled in a very piecemeal way between packages like DBI and those that build upon it like RJDBC, so that when I look at documentation such as ?dbConnect many of the options I need to specify are not even mentioned, and I've been working based off of miscellaneous Google search results related to these packages/errors.

得到了同样的错误。我也尝试了一些其他的变化/方法。我认为我混乱的一部分来自这样一个事实:文档包之间以一种非常零碎的方式处理DBI和那些像RJDBC建立它,所以当我看文档如? dbConnect的许多选项我需要指定甚至没有提到的,和我所工作的杂项Google搜索结果相关的这些包/错误。

One thread I found suggested trying

我找到一个线索，建议试试

.jaddClassPath( "xxxxx/postgresql-9.2-1002.jdbc4.jar" )

first, but that didn't seem to help.

首先，但这似乎没有帮助。

I also tried using

我也试着用

x <- PostgreSQL(max.con = 16, fetch.default.rec = 500, force.reload = FALSE)

to no avail and I experimented with RODBC as the driver.

但没有任何效果，我尝试用RODBC做司机。

UPDATE:

更新:

I tried using an older version of the driver (jdbc3 instead of jdbc4), restarting R, and detaching all unnecessary packages.

我尝试使用旧版本的驱动程序(jdbc3而不是jdbc4)，重新启动R，并释放所有不必要的包。

I was able to load the driver

我给司机上了车

> drv_custom <- JDBC(driverClass = "org.postgresql.Driver", classPath="/xxxxx/xxxxx/postgresql-9.3-1100.jdbc3.jar")

but I still can't connect...

但是我还是联系不上……

> con <- dbConnect(drv=drv_custom, "jdbc:postgresql://xxxxx.xxxxx.com", port=5439, uid="xxxxx", pwd="xxxxx")
Error in .verify.JDBC.result(jc, "Unable to connect JDBC to ", url) : 
Unable to connect JDBC to jdbc:postgresql://xxxxx.xxxx.com

2 个解决方案

#1

It took some troubleshooting on IRC, but here's what had to happen:

它在IRC上进行了一些故障排除，但是以下是必须发生的事情:

I needed to clear the workspace, detach RODBC and RJDBC, then restart
我需要清除工作空间，分离RODBC和RJDBC，然后重新启动。
Load RPostgreSQL
负载RPostgreSQL
Use only the generic driver
只使用通用驱动程序
Modify the syntax to

修改语法

con <- dbConnect(drv=drv_generic, "xxx.xxx.com", port=vvvv, user="ffff", password="ffff", dbname="ggg")

con <- dbConnect(drv=drv_generic， "xxx.xxx.com"， port=vvv, user="ffff"， password="ffff"， dbname="ggg")

Note: removing the jdbc:postgresql: part was key. Those would've been necessary with RJDBC, but RJDBC turned out to be an unnecessarily painful route.

注意:删除jdbc:postgresql:部分是关键。这些对于RJDBC来说是必要的，但是RJDBC被证明是一个不必要的痛苦路径。

#2

This works for me:

这工作对我来说:

library(RJDBC)
drv <- JDBC("org.postgresql.Driver","C:/R/postgresql-9.4.1211.jar")
con <- dbConnect(drv, url="jdbc:postgresql://host:port/dbname", user="<user name>", password="<password>")

The trick was to include port and dbname in the url. For some reason, jdbc:postgresql does not seem to like reading those information from the dbConnect parameters.

诀窍是在url中包含端口和dbname。出于某种原因，jdbc:postgresql似乎不喜欢从dbConnect参数读取这些信息。

If you are not sure what the dbname is, it is perhaps postgres.
如果您不确定dbname是什么，那么可能是postgres。
If you are not sure what the port is, it is perhaps 5432.
如果你不确定端口是什么，可能是5432。

So a typical call would look like:

所以一个典型的电话是这样的:

con <- dbConnect(drv, url="jdbc:postgresql://10.10.10.10:5432/postgres", user="<user name>", password="<password>")

You can get the jar file from https://jdbc.postgresql.org/

您可以从https://jdbc.postgresql.org/获得jar文件

#1