I am trying to clean up a Squid log file and I want to delete rows with a website containing /0/ in the 11th column. An example:Row1: column1, column2, column3...column10, ht*p://blah.com/page/230/0/blah0.htmlRow2: column1, column2, column3...column10, ht*p://narph0.net/page/328/narph.htmRow3: column1, column2, column3...column10, ht*p://www.yahata.org/things/time/0/yahata.phpRow4: column1, column2, column3...column10, ht*p://www.the.com/thethat/que303/yeah/main.phpIgnore the * in http because stackexchange thought those were real links.Essentially I want to delete rows 1 & 3 but leave rows 2 & 4. I have tried about every grep, awk and sed command that I could find or think of. I can get grep to delete if there are elements in column1 but none of the others. 
grep awk or sed a CSV Row containing a certain part of a web address
linux;sed;awk;grep
It seems you want the lines not having /0/ on the last column, you can do:grep -v '[^[:blank:]]*/0/[^[:blank:]]*$' file.txtExample:% grep -v '[^[:blank:]]*/0/[^[:blank:]]*$' fileRow2: column1, column2, column3...column10, ht*p://narph0.net/page/328/narph.htmRow4: column1, column2, column3...column10, ht*p://www.the.com/thethat/que303/yeah/main.phpOn the other hand, if you precisely want to match the 11-th column, you can do:grep -vE '^([^[:blank:]]+[[:blank:]]+){10}[^[:blank:]]*/0/[^[:blank:]]*$' file.txtExample: matching 5-th column% grep -vE '^([^[:blank:]]+[[:blank:]]+){4}[^[:blank:]]*/0/[^[:blank:]]*$' fileRow2: column1, column2, column3...column10, ht*p://narph0.net/page/328/narph.htmRow4: column1, column2, column3...column10, ht*p://www.the.com/thethat/que303/yeah/main.php