similar to: Caching of database values

I've been putting together a package that defined generic methods for database access. The packages is called "Rdbi." It borrows as much as possible from existing database packages / proposals. I'd like to start a discussion about the proposed interface. Here's what I've come up with so far: # # Rdbi: connectionMethods.R # dbConnect <- function(dbObj, ...)

I am currently experiencing concurrency issues after moving from MySQL to SQLite. My original program worked fined using MySQL but is now returning "SQLite3::BusyException" errors. The same result happens whether or not I enable the allow_concurrency flag. If I do manually acquire a lock on the SQLite DB the problem would disapear, but I thought that rails was supposed to handle this

All, I''ve written a simple job/opportunity tracking database app via RoR. I have about 10 internal users. Sometimes 2 people will want to update the same record at more or less the same time and they collide. In particular user 1 may edit a record, then get distracted, and finally an hour later they click save. During that hour user 2 may have pulled up the record, edited it, and

Hi everyone, I have a question regarding a C function of the "stats" package in R. I tried to understand the ?loglin? basic function of the ?stats? package implemented in R. The implemented function itself runs without any problem (perhaps see sample). When I ran it line by line it stopped at the lines 23-24 of the loglin-function; (the following line): z <- .Call(C_LogLin,

Dear R-Helpers, I've looked high and low for a function that provides frequencies, proportions and cumulative proportions side-by-side. Below is the table I need. Is there a function that already does it? Thanks, Bob > # Generate some test scores > myValues <- c(70:95) > Score <- ( sample( myValues, size=1000, replace=TRUE) ) > head(Score) [1] 77 71 81 88 83 93 > >

Yes, I am a newbie. I have a data.frame (MyTable) of 1445846 rows and 15 columns with character data. And a character vector (MyVector) of 473491 elements. I want simply to get a data.frame with the count of how many times each element of MyVector appears in MyTable. I've tried a loop with : for (i in 1 : length (myvector)) sum (MyTable== i) but it crashes my computer. I've also

Hi all, when i run this script: >read.table("Angelika.txt",header=T,sep="\t") >mytable=read.table("Angelika.txt",header=T,sep="\t") >for ( dye in c("A","B","C","F","G","K","L","M")) + { + for (cond in 1:8) + { + measurement =

Hello, Let's assume I have a vector of integers : > myvector <- c(1, 2, 3, 2, 1, 3, 5) My purpose is to obtain the cumulative distribution of these numerical data, i.e. something like : value nb_occur. <=1 2 <=2 4 <=3 6 <=4 6 <=5 7 For this, I create a table with ; > mytable <- table(myvector) 1 2 3 5 2 2 2 1 However, table() returns an array

I feel this is a very easy thing but I've never done it before and it is getting frustrating. I have a big data.frame (1445846 rows, 15 col) that looks like this: V1 V2 V3 V4 V5 1 home sister brother chair 0 2 cat dog animal 0 0 3 girl boy 0

Hello, In my script I would like to use a loop, which sorts the dataframe according to different columns, pointed by the string variable. id col1 col2 col3 1 10 0 4 8 2 11 1 2 2 3 12 0 8 3 4 13 0 5 5 Usually the order() function can be used like this: sorted = mytable**[order(column3) , ] which results in properly sorted table: **

I have created a function to do something: i <- factor(sample(c("A", "B", "C", NA), 793, rep=T, prob=c(8, 7, 5, 1))) k <- factor(sample(c("X", "Y", "Z", NA), 793, rep=T, prob=c(12, 7, 9, 1))) mytable <- function(x){ xtb <- x btx <- x # do more with x, not relevant here cat("The table has been created,

I have just started with Ruby and Rails and am still greatly confuse, finding the usual tutorials not much help. What I want to do is take two numbers from my database, multiply them together and display them in a list with a comma for the thousands separator. This would be very easy to do in a spreadsheet, so I assumed it would be easy to do in Ruby on Rails but I can''t work out how. I

Hi all, I'm sure this is simple but I don't get it. I have a table mytable<-c(rep("Disagree",37),rep("Agree",64)) table(mytable) this gives me Agree Disagree 64 37 but I didn't ask for it to be in alphabetic order. How can I get it in original order? Disagree Agree 37 64 Thanks, Jeff Jeffrey. M. Miller, PhD

Dear Friends, I am seeking for any help on an error message in lme functions. I use mixed model to analyze a data with compound symmetric correlation structure. But I get an error message: "Error in corMatrix.corCompSymm(object) : NA/NaN/Inf in foreign function call (arg 1)". If I change the correlation structure to corAR1, then no error. I have no clue how to solve this problem.

Getting the basic stuff to work is trivially simple. I can connect, and, for example, get everything in any given table. What I have yet to find is how to deal with parameterized queries or how to do a simple insert (but not of a value known at the time the script is written - I ultimately want to put my script into a scheduled task, so the analysis can be repeated on updated data either daily

Hello, I hope somebody can explain to me what''s going on here because I''m baffled! In a controller''s action I want to create a new order for a customer. Because I post back to the same action (not RESTful I know, but that''s for another day) I use code like this: def edit @order = Order.find_by_id(params[:id]) || Order.new ... end I

I've been playing around with various table tools, trying to construct a fairly simple cross-tab. It shouldn't be hard, but for some reason it turning out to be (for me). If I want to see how many men and how many women agree with a agree/disagree question (coded 1,0), I can do this: >attach(mydata) >mytable <- table(male, q1.bin) # gender and a binary response variable

Hi- Say I have a db with following schema: MyTable: Id, name, user_id, date User: id, name, description I know that I want to add "belongs_to" in my "user" model but how can I enforce a proper constraint on the user_id in "MyTable"? Is this done using a has_one in the "MyTable" model? Thanks! --~--~---------~--~----~------------~-------~--~----~ You

I am a relatively new user to R, and I am trying to learn more about converting data in an XML document into "2-dimensional format" such as a table or array. I might eventually wish to export this data into a relational database such as SQL, and/or to work with this data within the R package. My sample XML document is located at "

There is a little problem in handling logicals in RMySQL: # here is the MySQL connection > con <MySQLConnection:(1816,0)> # here is the data frame > print(a<-data.frame(x=c(TRUE,FALSE),y=c(FALSE,TRUE))) x y 1 TRUE FALSE 2 FALSE TRUE # as promised, the two data frame columns are identified as logicals and # the field types are set to tinyint > field.types <-