sql - Executing mySQL queries in R with MonetDB -


i new sql , using monetdb load large file r studio. have loaded data db using monetdb, , execute r code below on data in database:

my_selection <- db_data %>% group_by(id) %>%    tally(. , sort = true) %>%    top_n(100) %>%    select(id)  

basically, want group data "id", tally , sort it, , select 100 largest elements in it. equivalent of in sql?

i executing queries in following way in r:

my_selection <- dbgetquery(connection,"select * my_table [insert rest of code here]")  

that's depends on dbms you're using ,

sql-server :

select top 100 id,sum(yourothercolumn) sum_c yourtable group id order sum_c desc 

mysql :

select id,sum(yourothercolumn) sum_c yourtable group id order sum_c desc limit 100 

if it's else, tell me , i'll edit answer.


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