I am trying to create a SQLite table for each factor that I have in a R dataframe. I have created a for loop in an attempt to accomplish this, but when I include the dWriteTable() function it gives me an error. I believe it might have something to do with the "argument" but I can't say for certain.
Here is the code I currently have with the for loop:
# Connects to the database##
mydb <- dbConnect(RSQLite::SQLite(), "../Output/all_data.sqlite")
#Reads the selected table in database
mu_ut <- dbReadTable(mydb, "mu_ut")
for(i in unique(mu_ut$AnimalID)){
AnID <- paste("AnID", i, sep = ".")
dfname <- assign(AnID, mu_ut[mu_ut$AnimalID == i,])
dbWriteTable(conn = mydb, name = dfname, value = dat_csv,
field.types = c(DateAndTime = "DATETIME",
AnimalID = "CHAR",
Species = "CHAR",
Sex = "CHAR",
CurrentCohort = "CHAR",
BirthYear = "DATE",
CaptureUnit = "CHAR",
CaptureSubunit = "CHAR",
CaptureArea = "CHAR"))
}
I get the error message when I run it:
Error in (function (classes, fdef, mtable) :
unable to find an inherited method for function ‘dbWriteTable’ for signature ‘"SQLiteConnection", "data.frame", "data.frame"’
Any help would be appreciated!
Thank you!
When using dbWriteTable :
name is a character string giving the name of the table.
value is a dataframe with the values to write into the table
Try:
dbWriteTable(conn = mydb, name = AnID, value = mu_ut[mu_ut$AnimalID == i,],
field.types = c(DateAndTime = "DATETIME",
AnimalID = "CHAR",
Species = "CHAR",
Sex = "CHAR",
CurrentCohort = "CHAR",
BirthYear = "DATE",
CaptureUnit = "CHAR",
CaptureSubunit = "CHAR",
CaptureArea = "CHAR"))
Related
SQL and r ”update fields”
Can anyone help Me.? i am trying to update fields in a row in a table on a sql server.
I have tried to send a vector with that contains the data I want to update(new_d), but I get an error every time I try to send the object with sql query. If I hardcode it, it works fine and the update goes through to the server.
what goes wrong when it does not want to send the object and what does it take to make it work? so it can save the update to the server
Hope anyone can show me what i do worng.
library(tidyverse)
library(readxl)
library(DT)
library(RODBC)
library(DBI)
library(odbc)
library(dbplyr)
# Connection is working ---------------------------------------------------
conn <- dbConnect(odbc(),
Driver = "ODBC Driver 13 for SQL Server",
Server = "IP, PORT",
Database = "DBNAME",
UID = "USERNAME",
PWD = "PASSWORD")
new_d <- c(name = 'Rap',
dateOfBirth = '1938-06-06',
city = 'Hollywood',
gender = 'Man',
time() = 8,
feeling = 'Happy')
# NOT WORKING -------------------------------------------------------------
update_statement1 <- build_sql("UPDATE ShinyTest
SET Name =?, City =?, Gender =?,
DateOfBirth =?, Time =?, Feeling =?
WHERE ShinyUserID = 4", new_d, con = conn)
update_statement1
# NOT WORKING -------------------------------------------------------------
update_statement2 <- build_sql("UPDATE ShinyTest
SET Name = name, City = city, Gender = gender,
DateOfBirth = dateOfBirth, Time = time, Feeling = feeling
WHERE ShinyUserID = 4", new_d, con = conn)
update_statement2
# NOT WORKING -------------------------------------------------------------
update_statement3 <- build_sql("UPDATE ShinyTest
SET Name = 'name', City = 'city', Gender = 'gender',
DateOfBirth = 'dateOfBirth', Time = 'time', Feeling = 'feeling'
WHERE ShinyUserID = 4", new_d, con = conn)
update_statement3
# NOT WORKING -------------------------------------------------------------
update_statement4 <- build_sql("UPDATE ShinyTest
SET Name = $name, City = $city, Gender = $gender,
DateOfBirth = $dateOfBirth, Time = $time, Feeling = $feeling
WHERE ShinyUserID = 4", new_d, con = conn)
update_statement4
# WORKING -------------------------------------------------------------
update_statement5 <- build_sql("UPDATE ShinyTest
SET Navn = 'Rap', City = 'Hollywood', Gender = 'Mand',
DateOfBirth = '1938-06-06', Tid = '8', Feeling = 'Glad'
WHERE ShinyUserID = 4", con = conn)
update_statement5
# NOT WORKING -------------------------------------------------------------
DBI::dbSendQuery(conn, update_statement1)
DBI::dbSendQuery(conn, update_statement2)
DBI::dbSendQuery(conn, update_statement3)
DBI::dbSendQuery(conn, update_statement4)
# WORKING -------------------------------------------------------------
DBI::dbSendQuery(conn, update_statement5)
DBI::dbDisconnect(conn)
# The Error i get ---------------------------------------------------------
#Error: nanodbc/nanodbc.cpp:1655: 42000: [Microsoft][ODBC Driver 13 for SQL Server][SQL Server]Incorrect syntax near 'Rap'. [Microsoft][ODBC Driver 13 for SQL Server][SQL Server]Statement(s) could not be prepared.
#<SQL> 'UPDATE ShinyTest
# SET Navn = navn, City = city, Gender = gender,
# DateOfBirth = dateOfBirth, Tid = tid, Feeling = feeling
# WHERE ShinyUserID = 4('Rap', '1938-06-06', 'Hollywood', 'Mand', '8', 'Glad')'
I was trying to create a status bar in my for loop, but the status remains at 0%. I'm not sure what the issue could be.
n <- length(unique(mu_ut$AnimalID))
pb <- txtProgressBar(min = 0, max = n, style = 3)
for(i in unique(mu_ut$AnimalID)){
AnID <- paste("AnID", i, sep = ".")
assign(AnID, mu_ut[mu_ut$AnimalID == i,])
dbWriteTable(conn = db, name = AnID, value = mu_ut[mu_ut$AnimalID == i,],
field.types = c(DateAndTime = "DATETIME",
AnimalID = "CHAR",
Species = "CHAR",
Sex = "CHAR",
CurrentCohort = "CHAR",
BirthYear = "DATE",
CaptureUnit = "CHAR",
CaptureSubunit = "CHAR",
CaptureArea = "CHAR"), overwrite = TRUE)
Sys.sleep(1)
setTxtProgressBar(pb, i)
}
Is it a problem with the "i" argument in the setTxtProgressBar function?
Thank you in advance.
The issue is that setTxtProgressBar needs its value to be in the sequence min=0 to max=n, as set in your txtProgressBar. Since i is really one of the unique values within mu_ut$AnimalID, even if it is an integer, it is not clear that it is also in the range 0:n.
Try this.
ids <- unique(mu_ut$AnimalID)
pb <- txtProgressBar(min = 0, max = length(ids), style = 3)
for (ind in seq_along(ids)) {
id <- ids[ind]
AnID <- paste("AnID", id, sep = ".")
assign(AnID, mu_ut[mu_ut$AnimalID == id,])
dbWriteTable(conn = db, name = AnID, value = mu_ut[mu_ut$AnimalID == id,],
field.types = c(DateAndTime = "DATETIME",
AnimalID = "CHAR",
Species = "CHAR",
Sex = "CHAR",
CurrentCohort = "CHAR",
BirthYear = "DATE",
CaptureUnit = "CHAR",
CaptureSubunit = "CHAR",
CaptureArea = "CHAR"), overwrite = TRUE)
Sys.sleep(1)
setTxtProgressBar(pb, ind)
}
(This is very similar to #CareyCaginalp's comment.)
con <- dbConnect(odbc::odbc(),
Driver = "xxx",
Server = "xxxx",
Database = "xx", uid = "xxx", pwd = "xxx")
ABove is the function to call sql queries
and below is the code to call the table in R
fac <- dbGetQuery(con, "(select * from table where Category = '",input$Cat,"')") ##input$Cat is called in UI.R
But the above statement is not getting executed. Am i calling '",input$Cat,"' wrongly ?
I am attempting to write a dataframe using R to Teradata. The dataframe is wide in format (over 100 columns) and writing to Teradata implies declaring both the name and class of each variable. Note that the below data is just serving as an example.
iris$integerRandom <- seq_along(iris$Sepal.Length)
iris$Dates <- seq.Date(as.Date("2018-01-01"), by = "d", length.out = nrow(iris))
iris$Dates2 <- seq.Date(as.Date("2019-01-01"), by = "d", length.out = nrow(iris))
iris$Species <- as.character(iris$Species)
iris$characterRandom <- sample(letters, nrow(iris), replace = TRUE)
## Getting Numeric and Integer Names first
names_num <- names(iris)[which(sapply(iris, class) %in% c("integer", "numeric"))]
names_date <- names(iris)[which(sapply(iris, class) %in% "Date")]
names_character <- names(iris)[which(sapply(iris, class) %in% "character")]
## Generating variable names with corresponding variable types
paste(gsub("varchar(300)", '"varchar(300)"', gsub(",", " = varchar(300), ", toString(names_character))), "varchar(300)", sep = " = ")
paste(gsub(",", " = date", toString(names_date)), " = date")
paste(gsub("varchar(300)", '"float"', gsub(",", " = float, ", toString(names_num))), "float", sep = " = ")
Ideally, I would like the desired output to say
Species = "varchar(300)", characterRandom = "varchar(300)", and so forth. Note that the order in which the variables is important as the order matters when declaring the names and the types to Teradata (or SQL in this case) the code will probably work for both tools. So the order of the variable names along with
Sepal.Length and end with characterRandom.
I am wanting to convert a 2d lua table into a string, then after converting it to a string convert it back into a table using that newly created string. It seems as if this process is called serialization, and is discussed in the below url, yet I am having a difficult time understanding the code and was hoping someone here had a simple table.toString and table.fromString function
http://lua-users.org/wiki/TableSerialization
I am using the following code in order to serialize tables:
function serializeTable(val, name, skipnewlines, depth)
skipnewlines = skipnewlines or false
depth = depth or 0
local tmp = string.rep(" ", depth)
if name then tmp = tmp .. name .. " = " end
if type(val) == "table" then
tmp = tmp .. "{" .. (not skipnewlines and "\n" or "")
for k, v in pairs(val) do
tmp = tmp .. serializeTable(v, k, skipnewlines, depth + 1) .. "," .. (not skipnewlines and "\n" or "")
end
tmp = tmp .. string.rep(" ", depth) .. "}"
elseif type(val) == "number" then
tmp = tmp .. tostring(val)
elseif type(val) == "string" then
tmp = tmp .. string.format("%q", val)
elseif type(val) == "boolean" then
tmp = tmp .. (val and "true" or "false")
else
tmp = tmp .. "\"[inserializeable datatype:" .. type(val) .. "]\""
end
return tmp
end
the code created can then be executed using loadstring(): http://www.lua.org/manual/5.1/manual.html#pdf-loadstring if you have passed an argument to 'name' parameter (or append it afterwards):
s = serializeTable({a = "foo", b = {c = 123, d = "foo"}})
print(s)
a = loadstring(s)()
The code lhf posted is a much simpler code example than anything from the page you linked, so hopefully you can understand it better. Adapting it to output a string instead of printing the output looks like:
t = {
{11,12,13},
{21,22,23},
}
local s = {"return {"}
for i=1,#t do
s[#s+1] = "{"
for j=1,#t[i] do
s[#s+1] = t[i][j]
s[#s+1] = ","
end
s[#s+1] = "},"
end
s[#s+1] = "}"
s = table.concat(s)
print(s)
The general idea with serialization is to take all the bits of data from some data structure like a table, and then loop through that data structure while building up a string that has all of those bits of data along with formatting characters.
How about a JSON module? That way you have also a better exchangeable data. I usually prefer dkjson, which also supports utf-8, where cmjjson won't.
Under the kong works this
local cjson = require "cjson"
kong.log.debug(cjson.encode(some_table))
Out of the kong should be installed package lua-cjson https://github.com/openresty/lua-cjson/
Here is a simple program which assumes your table contains numbers only. It outputs Lua code that can be loaded back with loadstring()(). Adapt it to output to a string instead of printing it out. Hint: redefine print to collect the output into a table and then at the end turn the output table into a string with table.concat.
t = {
{11,12,13},
{21,22,23},
}
print"return {"
for i=1,#t do
print"{"
for j=1,#t[i] do
print(t[i][j],",")
end
print"},"
end
print"}"
Assuming that:
You don't have loops (table a referencing table b and b referencing a)
Your tables are pure arrays (all keys are consecutive positive integers, starting on 1)
Your values are integers only (no strings, etc)
Then a recursive solution is easy to implement:
function serialize(t)
local serializedValues = {}
local value, serializedValue
for i=1,#t do
value = t[i]
serializedValue = type(value)=='table' and serialize(value) or value
table.insert(serializedValues, serializedValue)
end
return string.format("{ %s }", table.concat(serializedValues, ', ') )
end
Prepend the string resulting from this function with a return, store it on a .lua file:
-- myfile.lua
return { { 1, 2, 3 }, { 4, 5, 6 } }
You can just use dofile to get the table back.
t = dofile 'myfile.lua'
Notes:
If you have loops, then you will have
to handle them explicitly - usually with an extra table to "keep track" of repetitions
If you don't have pure arrays, then
you will have to parse t differently,
as well as handle the way the keys are rendered (are they strings? are they other tables? etc).
If you have more than just integers
and subtables, then calculating
serializedValue will be more
complex.
Regards!
I have shorter code to convert table to string but not reverse
function compileTable(table)
local index = 1
local holder = "{"
while true do
if type(table[index]) == "function" then
index = index + 1
elseif type(table[index]) == "table" then
holder = holder..compileTable(table[index])
elseif type(table[index]) == "number" then
holder = holder..tostring(table[index])
elseif type(table[index]) == "string" then
holder = holder.."\""..table[index].."\""
elseif table[index] == nil then
holder = holder.."nil"
elseif type(table[index]) == "boolean" then
holder = holder..(table[index] and "true" or "false")
end
if index + 1 > #table then
break
end
holder = holder..","
index = index + 1
end
return holder.."}"
end
if you want change the name just search all compileTable change it to you preferred name because this function will call it self if it detect nested table but escape sequence I don't know if it work
if you use this to create a lua executable file that output the table it will ge compilation error if you put new line and " sequence
this method is more memory efficient
Note:
Function not supported
User data I don't know
My solution:
local nl = string.char(10) -- newline
function serialize_list (tabl, indent)
indent = indent and (indent.." ") or ""
local str = ''
str = str .. indent.."{"
for key, value in pairs (tabl) do
local pr = (type(key)=="string") and ('["'..key..'"]=') or ""
if type (value) == "table" then
str = str..nl..pr..serialize_list (value, indent)..','
elseif type (value) == "string" then
str = str..nl..indent..pr..'"'..tostring(value)..'",'
else
str = str..nl..indent..pr..tostring(value)..','
end
end
str = str:sub(1, #str-1) -- remove last symbol
str = str..nl..indent.."}"
return str
end
local str = serialize_list(tables)
print('return '..nl..str)