我需要安装 RMySQL 包，但我在安装包菜单上找不到它，甚至选择不同的镜像它也不起作用……我该怎么办？
> install.packages("RMySQL")
Installing package(s) into ‘C:/Users/admin/Documents/R/win-library/2.15’
(as ‘lib’ is unspecified)
package ‘RMySQL’ is available as a source package but not as a binary
Warning message:
package ‘RMySQL’ is not available (for R version 2.15.2)