Thursday, 15 March 2012

sqldf select statements in R not working? -



sqldf select statements in R not working? -

i have dataframe myframe 8 variables in r. load sqldf bundle using library(sqldf). run command:

proxyframe = sqldf("select a, b, c, d, e myframe c > 1000")

however, when @ proxyframe using view(proxyframe) see there clear instances of rows included c < 1000. did farther investigations , found reason statements like:

"0" < 6 # returns true "22" > 6 # returns false

i'm looking general tips or ideas @ might causing select statements homecoming odd dataframes, , if has r's weird utilize of comparing operators. fear somehow column c character , right comparing operator isn't beingness applied---though don't have much experience how r works under cover or how bundle works.

cast character column real:

> df <- data.frame(a = "22", stringsasfactors = false) > sqldf("select * df cast(a real) > 6") 1 22

r sqldf

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