tree 5c189e4dbb11bbc8d76cf89ad1f0cc99c3f1b2a0
parent 4231002d8062e0daa0ff67fa5c249b418d99b5f2
author Hao Zhu <haozhu233@gmail.com> 1596998290 -0400
committer Hao Zhu <haozhu233@gmail.com> 1596998290 -0400

Fix bugs in remove_column