similar to: How can I change SQLite cache size for R session?

Displaying 20 results from an estimated 2000 matches similar to: "How can I change SQLite cache size for R session?"

2007 Oct 22
3
RSQLite indexing
I am trying to use RSQLite for storing data and I need to create indexes on two variables in the table. It appears from searching the web that the CREATE INDEX operation in SQLite is relatively slow for large files, and this has been my experience as well. The two index variables are crossed. One has about 350,000 levels [yes, it's genetic association data]. The other will have about
2004 Nov 25
3
Searching for a string in RSQLite
I'd like to search for a particular string in an SQLite database using RSQLite, but I'm running into problems constructing the query properly, because of embedded quotes and parens in the string. Is there a function that escapes these for me, or some other fixup that would let me do the queries below? In the real situation I don't have control over what strings get searched for.
2011 Feb 28
1
Data type problem when extract data from SQLite to R by using RSQLite
Hi there, When I extract data from SQLite to R, the data types (or modes) of the extracted data seems to be determined by the value of the first row. Please see the following example. When I put the missing values first, the column extracted is of the mode character. > str(dbGetQuery(sql.industry, + "select pya_var from annual_data3 + order by
2009 Mar 30
1
Importing csv file with character values into sqlite3 and subsequent problem in R / RSQLite
Dear all, I'm trying to import a csv file into sqlite3 and from there into R. Everything looks fine exepct that R outputs the character values in an odd fashion: they are shown as "\"CHARACTER\"" instead of "CHARACTER", but only if I show the character variable as a vector. Does someone know why this happens? Below is a sample code. The first part is written in
2010 Jul 09
2
Compress string memCompress/Decompress
Hello, I would like to compress a long string (character vector), store the compressed string in the text field of a SQLite database (using RSQLite), and then load the text back into memory and decompress it back into the the original string. My character vector can be compressed considerably using standard gzip/bzip2 compression. In theory it should be much faster for me to compress/decompress
2009 Nov 30
1
RSQLite does not read very large values correctly
Hello, I am trying to import data from an SQLite database to R. Unfortunately, I seem to get wrong data when I try to import very large numbers. For example: I look at the database via SQLiteStudio(v.1.1.3) and I see the following values: OrderID Day TimeToclose 1 2009-11-25 29467907000 2 2009-11-25 29467907000 3 2009-11-25 29467907000 Now I run this R Code: >
2009 Dec 18
1
The RSQLite version of dbGetQuery drops colums
Hi all, I just noticed (the hard way of course) that when a query returns 0 rows, the columns in the resulting data.frame get dropped as well. See the following example code (where conn is an active connection to an SQLite db): > dbGetQuery(conn, "select 1 as hey, 2 as ho where 1") hey ho 1 1 2 > dbGetQuery(conn, "select 1 as hey, 2 as ho where 0") data frame
2006 Mar 15
3
"\r" with RSQLite
What am I doing wrong, or is the \r that I'm getting in the example below a bug? > a <- (1:10) > b <- (LETTERS[1:10]) > df <- as.data.frame(cbind(a, b)) > > df a b 1 1 A 2 2 B 3 3 C 4 4 D 5 5 E 6 6 F 7 7 G 8 8 H 9 9 I 10 10 J > library(RSQLite) > drv <- dbDriver("SQLite") > con <- dbConnect(drv, dbname = "Test")
2006 Mar 15
3
"\r" with RSQLite
What am I doing wrong, or is the \r that I'm getting in the example below a bug? > a <- (1:10) > b <- (LETTERS[1:10]) > df <- as.data.frame(cbind(a, b)) > > df a b 1 1 A 2 2 B 3 3 C 4 4 D 5 5 E 6 6 F 7 7 G 8 8 H 9 9 I 10 10 J > library(RSQLite) > drv <- dbDriver("SQLite") > con <- dbConnect(drv, dbname = "Test")
2008 May 12
1
Insert a recorde into a table using SQL
Dear list, I want to insert a recorde into a SQLite table by dbGetQuery(), but there is a problem when the value contains quotation mark. > dd<-data.frame(txt=c("having both ' and \" in character.","OK")) > library(RSQLite) Loading required package: DBI > con<-dbConnect(dbDriver("SQLite"),":memory:") >
2006 Jan 19
0
RSQLite
Version 0.4-1 of the RSQLite package has been uploaded to CRAN. RSQLite embeds the SQLite engine in R (see http://www.sqlite.org) Changes include: * Fixed problems exporting/importing NA's * An new experimental dbWriteTable() method to create SQLite tables from simple files (delimited unquoted fields), e.g., > dbWriteTable(con, "table_name", "file_name", ...)
2006 Jan 19
0
RSQLite
Version 0.4-1 of the RSQLite package has been uploaded to CRAN. RSQLite embeds the SQLite engine in R (see http://www.sqlite.org) Changes include: * Fixed problems exporting/importing NA's * An new experimental dbWriteTable() method to create SQLite tables from simple files (delimited unquoted fields), e.g., > dbWriteTable(con, "table_name", "file_name", ...)
2012 Mar 27
1
RSqlite UPDATE command problem
All: I am using RSqlite and want to be able to update individual values in a record, such as with this simple example: library(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))
2013 Feb 12
0
How do I solve a disk I/O error with RSQLite?
Hi there, I had an error when using RSQLite. My code and the error message are the following: > dbGetQuery(sql.dispersion, + "create table monthly_data_temp as + select a.*, b.industry + from monthly_data as a left join + siccd_industry_ff49 as b + on a.siccd = b.siccd + order by permno, date") Error
2010 May 10
3
dbSendQuery with R variables
Rhelpers: I'd like to modify this RSQLite statement: rs_stations<-dbSendQuery(con_stations, "select * from stations") so that stations is actually an R variable, e.g.: stations=c("stationA","stationB") How would I modify the above statement to query from stations[[1]] (aka "stationA")? --j
2012 Feb 21
1
sqlite create new unique id
Hi everyone, I am trying to insert a row in sqlite table with my own unique id. I want to create unique id using sqlite internal function last_insert_rowid() which returns the next max rowid of the table which is always unique. I tested this using sqlite and it works fine but when i run the same query using RSQlite from r prompt, my query doesn't create new unique id. last_insert_rowid()
2020 Oct 08
0
Lahman Baseball Data Using R DBI Package
Hi Philip, You've probably realized by now that R doesn't like column names that start with a number. If you try to access an R-dataframe column named 2B or 3B with the familiar "$" notation, you'll get an error: > library(DBI) > library(RSQLite) > con2 <- dbConnect(SQLite(), "~/R_Dir/lahmansbaseballdb.sqlite") > Hack12Batting <-
2010 Nov 15
5
How to Read a Large CSV into a Database with R
Hi, I'm working in R 2.11.1 x64 on Windows x86_64-pc-mingw32. I'm trying to insert a very large CSV file into a SQLite database. I'm pretty new to working with databases in R, so I apologize if I'm overlooking something obvious here. I'm trying to work with the American Community Survey data, which is two 1.3GB csv files. I have enough RAM to read one of them into memory,
2020 Oct 08
1
Lahman Baseball Data Using R DBI Package
This is really a feature of SQL, not R. SQL requires that you double quote column names that start with numbers, include spaces, etc., or that are SQL key words. E.g., > d <- data.frame(Order=c("sit","stay","heel"), Where=c("here","there","there"), From=c("me","me","you")) >
2013 Jul 15
2
Serialize data.frame to database
Dear R-Users, I need a very fast and reliable database solution so I try to serialize a data.frame (to binary data) and to store this data to an SQLite database. This is what I tried to do: library(RSQLite) con <- dbDriver("SQLite") db <- dbConnect(con, "test") dbSendQuery(db, 'CREATE TABLE frames("simID" INT, "data" BLOB)') data.bin <-