Add a section to Impala about cleaning up your metadata. If you create a table in Impala and then drop the Hive metadata, you will need to invalidate the Impala metadata.
impala_con <- dbConnect(odbc::odbc(), "Impala")
dbWriteTable(impala_con, "mtcars", mtcars)
hive_con <- dbConnect(odbc::odbc(), "Hive")
dbRemoveTable(hive_con, "mtcars")
dbReadTable(impala_con, "mtcars") # succeeds
dbExistsTable(impala_con, "mtcars") # fails
dbGetQuery(odbcCon, "INVALIDATE METADATA mtcars")
dbExistsTable(impala_con, "mtcars") # succeeds
This happens because dropping the Hive metadata does not drop the Impala metadata. More information can be found here.