CODEWITHSUNDEEP
pythoncsv
Damien Cresswell
Damien Cresswell

Reputation: 23

How do i get python to remove the row i search for from csv file

I am able to edit and add new entries but everytime i try to delete the row i search for, it wipes the whole files data.

I need it to just remove that row of data without losing the rest of the rows.

    import csv,os,sys

def helper(file):
    o=csv.reader(open(file,"r"))
    for row in o:
        print row

def delete(filename):
    found=False
    f1=csv.reader(open(filename,'r'))
    f2=csv.writer(open("temp.csv",'a'))
    rid=raw_input("Enter name to find record:")
    for row in f1:
        if rid in row[0]:
            found=True
            f2.writerow()
            print rid, "has been deleted from the database!"
        else:
            found=False
    if found==False:
        print "That name isn't in our database!"
        z=raw_input("Please enter 1 to retry, 2 to return to log in, or 3 to close program:")
        if z=="1":
            delete(filename)
        if z=="2":
            import program
        if z=="3":
            exit




helping=raw_input("Do you require any help with using this feature?Type y for yes or just hit enter to continue:")
if helping=="y":
    helper('deletehelp.txt')

delete("custdet.csv")       
os.remove("custdet.csv")
os.rename("temp.csv","custdet.csv")     #This is the file rename that I mentioned above.
restart=raw_input("Would you like to return to the main menu? Please type Y or just hit enter to exit:")
if restart=="y":
    import program
else: exit

Upvotes: 0

Views: 370

Answers (3)

mhawke
mhawke

Reputation: 87134

Change the section containing the for loop to this:

    for row in f1:
        if rid in row[0]:
            found=True
            print rid, "has been deleted from the database!"
        else:
            f2.writerow(row)

The changes:

  • Actually write the row if rid is not in row[0]
  • Don't reset the found flag to False

The rest of the code also needs some work:

  • Recursion is not the best way to handle retries, use a loop instead.
  • import program to return to the login ????? That's not going to work. Perhaps you should just return from the function.
  • There is coupling between delete() and the calling code which relies on a file named temp.csv being created. It would be much better if delete() performed the renaming of the temporary file itself.

Upvotes: 0

FatmaT
FatmaT

Reputation: 255

import csv,os,sys

def helper(file):
    o = csv.reader(open(file,"r"))
    for row in o:
        print row

def delete(filename):
    f1 = csv.reader(open(filename,'r'))
    f2 = csv.writer(open("temp.csv",'a'))
    rid = raw_input("Enter name to find record:")
    found = False
    for row in f1:
        if rid not in row[0]:
            f2.writerow(row)
        else:
            found = True
            print rid, "has been deleted from the database!"

    if found == False:
        print "That name isn't in our database!"
        z = raw_input("Please enter 1 to retry, 2 to return to log in, or 3 to close program:")
        if z == "1":
            delete(filename)
        if z == "2":
            import program
        if z == "3":
            exit

Upvotes: 1

emvee
emvee

Reputation: 4449

You never actually write to the new csv file.

Look at the main filter/copy loop:

# for every row in the input file
for row in f1:
        # Is this the/a record to delete?
        if rid in row[0]:
            # yes!
            found=True
            # then we do not write anything to the output file (???)
            f2.writerow()
            print rid, "has been deleted from the database!"
        # no else part, so no nothing gets done with
        # the input row `row` ...

So you'll end up with an empty output file ...

Upvotes: 1

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