st: read two kinds of files into a master file

[Huaandrew <andrew0845@hotmail.com>]

Hello,

I am using Stata 12 to create a large master file which is appended by 3,000 csv files. The problem is that the 3,000 files have two kinds of structure: one has only one column and the other two columns. For the two-column files, the first column is character used as note for the second column, which is numeral, such as 12,356. For the one-column files, the column is numeral as in the two-column file. What Stata commands I should use to distinguish the two kinds of files and if it's one-column file, let Stata create a new column which is used as note as in the two-column file.

The original code without distinguishing the two kinds of files is as follows. Stata clashed when reading the first one-column file after reading several two-column files. 

cd d:\Stata_Data\found
! dir *.csv /a-d /b>d:\Stata_Data\filelist.txt

file open myfile using d:\Stata_Data\filelist.txt, read
file read myfile line
insheet using `line', comma
gen hpl_id = substr("`line'",1,22)
save `line'.dta, replace
save master_data.dta, replace
drop _all
file read myfile line

while r(eof)==0{
insheet using `line', comma
gen hpl_id = substr("`line'",1,22)
save `line'.dta, replace
append using master_data.dta
save master_data.dta, replace
drop _all
file read myfile line
}

Thanks!
Andrew 		 	   		  
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