simp only [nrows, renameColumns, Schema.length_eq_List_length]
η : Type u_η
dec_η : DecidableEq η
sch : Schema
t✝ : Table sch
ccs✝ : ActionList Schema.renameColumnCN sch
⊢ nrows (renameColumns t✝ ccs✝) = nrows t✝
η : Type u_η
dec_η : DecidableEq η
sch : Schema
t✝ : Table sch
ccs✝ : ActionList Schema.renameColumnCN sch
⊢ List.length (List.map (Row.renameCells ccs✝) t✝.rows) = List.length t✝.rows