add db_write_table.MySQLConnection

[kongdd]

By adding this function, RMySQL will be alive again. I have tested the function of copy_to, compute, collaps, collect, rows_append.

Only one line modified. It seems that table_ident_to_id(table) not work for RMySQL backend. When table_ident_to_id(table) changes to table_name, issue is solved.

[kongdd]

This PR will solve the issues of r-dbi/RMySQL#230, tidyverse/dplyr#5329.

[hadley]

I no longer see much of a performance difference. Are you sure that this is still necessary?

library(DBI)
con_maria <- dbConnect(
  RMariaDB::MariaDB(),
  dbname = "test",
  username = "root",
  password = "",
  load_data_local_infile = TRUE
)
system.time(dbWriteTable(con_maria, "diamonds", ggplot2::diamonds))
#>    user  system elapsed 
#>   0.258   0.059   0.702
dbRemoveTable(con_maria, "diamonds")

^{Created on 2023-12-21 with reprex v2.0.2.9000}

library(DBI)
con_mysql <- dbConnect(
  RMySQL::MySQL(),
  dbname = "test",
  username = "root",
  password = ""
)
system.time(dbWriteTable(con_mysql, "diamonds", ggplot2::diamonds))
#>    user  system elapsed 
#>   0.369   0.018   0.594
dbRemoveTable(con_mysql, "diamonds")
#> [1] TRUE

^{Created on 2023-12-21 with reprex v2.0.2.9000}

[hadley]

Regardless, after #1396, this will need some changes, and overall I think I'd prefer to figure out how to reduce some of the duplication across backends here. So if it's still a problem for you, please file an issue and I'll tackle it next year.