我的数据包含特殊字符，比如德语元音变音符。

p=structure(list(ppl_code = c(992621L, 992381L, 992136L, 991989L, 
991898L, 991759L, 991681L, 991593L, 991294L, 991036L, 990934L, 
990751L, 990535L, 990411L, 990182L, 989507L), proj_name = c("klo", 
"Dalbygda", "Oosterhorn", "Hån", "Yatir", "Montigny la Cour", 
"Valle Hermoso", "Acciona Honawad - 120 MW", "Apfeltrang", "RiaBlades", 
"General Acha", "Lindau-Böhlitz", "Apfeltrang", "Alcazar Round 2", 
"Peckelsheim", "Linnich 3")), .Names = c("ppl_code", "proj_name"
), row.names = 15:30, class = "data.frame")

当我尝试将其写入mysql数据库时：

conn <- dbConnect(
       drv = RMySQL::MySQL(),
       dbname = "mydb",
       host = "#####",
       username = "#####",
       password = "#####")
dbWriteTable(conn, value = p, name = "MyTable",row.names=FALSE)

我得到了编码错误：

could not run statement: Invalid utf8 character string: 'Lindau-B'

我查了好几篇关于这个问题的帖子，像这里和这里，但它们都是一般性的解释，没有一个明确的解决办法！有谁能帮我提出一个明确的问题来解决这个问题？