install.packages("RODBC")
Warning: 无法在貯藏處https://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib中读写索引:
  无法打开URL'https://mirrors.tuna.tsinghua.edu.cn/CRAN/src/contrib/PACKAGES'
Warning: 无法在貯藏處https://mirrors.tuna.tsinghua.edu.cn/CRAN/bin/windows/contrib/3.2中读写索引:
  无法打开URL'https://mirrors.tuna.tsinghua.edu.cn/CRAN/bin/windows/contrib/3.2/PACKAGES'
Warning message:
package ‘RODBC’ is not available (for R version 3.2.4 Revised)