R to MySQL query - mysql

Question

I got a data frame in R querying a SQL Server DB, Now I want to loop on each line and insert it to MySQL DB
Tried with dbwritetable but it didn't work
library(RODBC)
library(odbc)
library(RMySQL)
con <- dbConnect(odbc(),
Driver = "SQL Server",
Server = "XX",
Database = "XX",
UID = "XX",
PWD = "XX",
Port = XX)
mydb = dbConnect(MySQL(), user='XX', password='XX', dbname='YY', host='YYY')
resultset <- dbGetQuery(con, "SET NOCOUNT ON
DECLARE #StartDate DateTime
DECLARE #EndDate DateTime
SET #StartDate = dateadd(d,-1,getdate())
SET #EndDate = getdate()
SET NOCOUNT OFF
SELECT …..
LEFT JOIN ... ON ….
LEFT JOIN …. ON x.Key = y.Key
WHERE temp.StartDateTime >= #StartDate")
nrows <- nrow(resultset)
colnames(resultset) <- c("tagName", "date_inserted","value") `
So in here I got my result, in resultset but I don't know how to insert the resulset in MySQL
dbWriteTable(mydb, name='data', value=resultset[0,],append=TRUE)
dbReadTable(mydb, "data")
I Expect to insert the data, but I don't know should it be a for loop (for each line a query) or how is it done
More details with this images :
This is my data set
This is MySQL DB structure

Answer 1

Try using a parameterized insert using the RODBCext package. I have used the following function in the past.
This will append records into your database
library(RODBC)
library(RODBCext)
First we need to connect to the database using RODBC.
sql.driver = "MySQL ODBC 5.3 ANSI Driver" # need to figure the version out
sql.server = "your_server_here"
sql.port = "3306" # or whatever your port number is
sql.user = "your_user_name_here"
sql.pass = "your_password_name_here"
sql.db = "your_database_name_here"
con.string = paste0("Driver=", sql.driver, ";",
"Server=", sql.server, ";",
"Port=", sql.port, ";",
"Uid=", sql.user, ";",
"Pwd=", sql.pass, ";",
"Database=", sql.db, ";")
ch = odbcDriverConnect(con.string)
Then here is the custom function saveTable(). You will want to run this with your specific inputs, defined below.
saveTable <- function(con, table_name, df) {
# con = the ODBC connection (e.g., ch)
# table_name = the SQL database table to append to
# df = the data.frame() to append
sql_code = paste("INSERT INTO",table_name,"(",paste(colnames(df),collapse=", "),") VALUES (",paste(rep("?",ncol(df)),collapse=","),")")
sqlExecute(con, sql_code, df)
}