Displaying 20 results from an estimated 44 matches for "dbreadtable".
2012 Nov 02
1
can not read table in dbReadTable
> tbs<-dbListTables(con)
>
> tbs
[1] "lowend" "time" "week30" "week33" "week39" "week42"
> my.data.copy <- dbReadTable(tbs, "week42")
Error in function (classes, fdef, mtable) :
unable to find an inherited method for function "dbReadTable", for signature "character", "character"
I have created tables in db. but there is this error show up when I try to read the table in...
2012 Nov 06
0
How to read all table in r using dbreadTable, autimatically read in whenever I save new table in SQLite db
HI,
I got the problem.
I use the following query to read table individually, how can I read all tables autimatically rather than typing "week42" "week33" in dbReadTable?
library(RSQLite)
library(sqldf)
drv <- dbDriver("SQLite")
con<-dbConnect(drv, "sqlite.db")
dbListTables(con)
#dbRemoveTable(con, "week39")
dbDisconnect(con)
week42<- dbReadTable(con, "week_42")
week33<- dbReadTable(con, "week33")
w...
2011 Jul 01
1
RMySQL, RODBC, dbReadTable and ISO-8859-1 (Spanish data)
Hello R users,
I am reading data into R from RMySQL or SQLite databases which are in
Spanish language. I am using RMySQL library and function dbReadTable but I
could not get characters with ñ and tilde, instead R does put ?.
In the past I could manage it modifying the R options as (using windows):
op <- options()
op$encoding <- "iso-8859-1"
options(op)
but now in ubuntu it did not work. I am working in ubuntu 10.04 and R
2.10.1....
2009 Dec 24
1
How to dbReadTable() only a limited number of rows? (RMySQL)
I only want to load a limited number of rows by dbReadTable(). I don't
see an option in the help. Is there an option to do so?
2008 Nov 06
1
RMySql inserts \r when using dbWriteTable
I am using R 2.8 and the latest versions of RMySQL on a Windows XP 64 bit
machine.
I was wondering if someone could help me figure out how to use dbWriteTable
without inserting \r into my table. Consider the following code snippet,
which is
run after I connect to my database.
myDFOut = dbReadTable(conn, "myDF")
print(myDFOut)
myDFIn = data.frame(x=paste("x", 1:5, sep = ""), y = paste("y", 1:5, sep =
""))
dbWriteTable(conn, name= "myDF", value = myDFIn, row.names=F, append =TRUE,
eol = "\r\n" )
myDFOut = dbReadTable(conn, &...
2005 Feb 01
2
How to get a table of MySQL database as a matrix variable in R
It seems that the dbReadTable() method provided by RMySQL could not
get rid of the headers, neither the index column... So
1. Can I use read.table() method to get a table of MySQL database?
>From the help document the argument of 'file' of read.table() method
could be a connection...
2. How can I obtain a matrix fr...
2004 Mar 05
1
Slow reshape from 5x600000 to 6311 x 132
I have a dataset that's a few hundred thousand rows from a database
(read in via dbreadTable). The database is like:
> str(measures)
`data.frame': 609363 obs. of 5 variables:
$ vih.id : int 1 2 3 4 5 6 7 8 9 10 ...
$ vi.id : int 1 2 3 4 5 6 7 8 9 10 ...
$ vih.value: chr "0" "1989" "0" "N/A" ...
$ vih.date : chr &qu...
2008 Aug 11
1
Unwanted carriage returns storing dataframes with dbWriteTable
If I save a dataframe with a character-typed last column to a relational
database with dbWriteTable, the values in the last column of the
resulting table in the database will have a '\r' (carriage return)
appended. If I read back the dataframe with dbReadTable the last column
in the resulting dataframe has also '\r' appended (see protocol below).
Setting or unsetting sql-mode (in the SQL-Server Version 5.0) to or from
'NO_BACKSLASH_ESCAPE' has no effect on this behavour ? How can I avoid
these unwanted '\r'-tail ?
Hansruedi...
2002 Dec 18
1
A little problem handling logicals in RMySQL under R1.6.1
...s to 0s and 1s.
# And logically, the infile is written in TRUE and FALSE and finally, in MySQL
# all becomes zero. Here is what we get in MySQL:
# row_names x y
# 1 0 0
# 2 0 0
#
# So, logically this is what we get back in R:
> dbWriteTable(con,"test",a)
[1] TRUE
> aa<-dbReadTable(con,"test")
> aa
x y
1 0 0
2 0 0
>
# and this is clearly not what we want...
#
# as a crude patch I added for (i in 1:length(value)) if (class(value[[i]])=="logical") class(value[[i]])<-"integer"
# before i <- match("row.names", ... in mysqlW...
2007 Oct 01
2
xyplot
...out graphs but empty! COuld you help me plase on that? Thank you in advance
z1 <- dbConnect(MyData, "something", "A1", "A2")
for (tt in c("xyz", "abc", "m1")) {
message(paste("Here", tt, "!!!"))
mydata <- dbReadTable(z1, tt)
jpeg(file=paste("D:/", tt, ".jpg", sep=""), width=00, height=100)
plot.method="bitmap"
xyplot(MyVALUE ~ MyNo | as.character(ID), data = mydata, main = tt, xlab = " ", ylab = " ", type="l")
dev.off()
}
-----...
2001 Mar 19
3
generic database access methods
...n object.
#
dbListTables <- function(conn, ...) UseMethod("dbListTables")
#
# Output a list of table names associated with the connection object.
# Output should look like output from ls().
#
dbListTables.default <- function(conn, ...) stop("Invalid connection
object")
dbReadTable <- function(conn, ...) UseMethod("dbReadTable")
#
# Analog of the read.table() function. Returns a data frame. Some
# facility for converting DB types to R types is helpfull. Generally,
# this will just pass a "select * from mytable" to dbSendQuery() which
# returns the da...
2010 Apr 30
0
RMySQL and dates
I am trying to read and write database tables that have a date field in
them.
I am constructing a data.frame, then using dbWriteTable to create the
table and dbReadTable to read it.
>datatbl<-data.frame( dates, trialnum, fooddel, ethdel, trialtime,
trialtype, deliveries, food, ethanol, fcumrec, dcumrec, rrf, rrd)
>ifelse(startdate==filelist, filetbl<-datatbl,filetbl<-rbind(filetbl,
datatbl))
>dbWriteTable(con, subj, as.data.frame(filetbl),...
2005 Apr 02
2
RMySQL question
Dear List,
I have this little problem:
I work with adiacency matrix like:
data me you
me 0 1
you 1 0
I store those matrix in a mysql database
actually I use RMySQL with:
res<-dbSendQuery(connection, "SELECT * FROM table")
myDataFrame<-fetch(res)
to retrive the table, and I have
data me you
1 io 0 1
2 tu 1 0
I would like the first column to be seen
2012 Mar 27
1
RSqlite UPDATE command problem
...ry(RSQLite)
drv<-dbDriver("SQLite")
con<-dbConnect(drv,"test.db")
my.data<-data.frame(countries=c("US","UK","Canada","Australia","NewZealand"),vals=c(52,36,74,10,98))
dbWriteTable(con,"testtable",my.data)
q<-dbReadTable(con,"testtable")
q
countries vals
1 US 52
2 UK 36
3 Canada 74
4 Australia 10
5 NewZealand 98
So, say, I want to change the value for NewZealand to '21' from '98'
I've tried something like this:
sql<-"UPDATE testtable SET va...
2012 Nov 06
1
how Can make function for selecting the products
HI.
I make this code:
getdata<-function('a','b','c' ,'d','e','f'){
drv <- dbDriver("SQLite")
con<-dbConnect(drv, "sqlite.db")
lt<-dbListTables(con)
myf<-data.frame(NULL)
for (i in 1:length(lt))
{
myfile<-dbReadTable(con,lt[i])
myfile1<-myfile[-c(14:44)]
myfile1$MODEL<-gsub(" ", "", myfile1$MODEL)
library(RSQLite)
library(sqldf)
my_file<-sqldf("SELECT *
FROM myfile1 where MODEL in ('a','b','c' ,'d','e','f')")
my.file.s...
2005 Apr 04
2
mysql retrive question
hello R-Users,
I have this simple but not for me question:
I do:
> res<-dbSendQuery(con, "SELECT * FROM tabellaProva")
> myDataFrame<-fetch(res)
> myDataMatrix<-as.matrix(myDataFrame[,-1])
> namerows(myDataMatrix)<-as.character(myDataFrame[,1])
and I have:
io tu
io "0" "1"
tu "1" "0"
my problem is that the
2005 Oct 27
2
RSQLite problems
...dbms")
> data (barley)
> dbWriteTable (db, "barley", barley, overwrite = TRUE)
[1] TRUE
> barley[1:3,]
yield variety year site
1 27.00000 Manchuria 1931 University Farm
2 48.86667 Manchuria 1931 Waseca
3 27.43334 Manchuria 1931 Morris
> dbReadTable (db, "barley")[1:3,]
yield variety year__1 site
1 27.00000 Manchuria 1931 University Farm\n
2 48.86667 Manchuria 1931 Waseca\n
3 27.43334 Manchuria 1931 Morris\n
> barley$site <- as.character (barley$site)
> barley$site[1] <- &qu...
2007 Mar 20
1
RMySQL load error
...t;
[1] "dbConnect"
[1] "dbConnect"
[1] "dbDisconnect"
[1] "dbSendQuery"
[1] "dbGetQuery"
[1] "dbGetException"
[1] "dbGetInfo"
[1] "dbListResults"
[1] "summary"
[1] "dbListTables"
[1] "dbReadTable"
[1] "dbWriteTable"
[1] "dbWriteTable"
[1] "dbExistsTable"
[1] "dbRemoveTable"
[1] "dbListFields"
[1] "dbCommit"
[1] "dbRollback"
[1] "dbCallProc"
[1] "MySQLResult"
[1] "dbClearResult"...
2005 Mar 09
1
RMySQL installed but not availalable
...quot;dbConnect"
> [1] "dbDisconnect"
> [1] "dbSendQuery"
> [1] "dbGetQuery"
> [1] "dbGetException"
> [1] "dbGetInfo"
> [1] "dbListResults"
> [1] "summary"
> [1] "dbListTables"
> [1] "dbReadTable"
> [1] "dbWriteTable"
> [1] "dbExistsTable"
> [1] "dbRemoveTable"
> [1] "dbListFields"
> [1] "dbCommit"
> [1] "dbRollback"
> [1] "dbCallProc"
> [1] "MySQLResult"
> [1] "dbClearResult...
2020 Oct 02
3
Lahman Baseball Data Using R DBI Package
...eave there two out but I get error messages (in red) when I include 2B/3B or X2B/X3B.
Can anyone give me some direction?
Thanks,
Philip Heinrich
***************************************************************************************************************************************************
tail(dbReadTable(Lahman,"batting"))
ID playerID yearID stint teamID team_ID lgID G G_batting AB R H X2B X3B HR RBI SB
107414 107414 yastrmi01 2019 1 SFN 2920 NL 107 NA 371 64 101 22...