How to find a number with 11 digits ignoring a number with 12 digits

alireza.sabeti · Mar 04, 2015#12015-03-04T23:56+00:00

Hello all,
it may odd to ask a question from you, but I'd like to know that. Please suppose I have a text file with 10 million records and each lines contain one mobile number with 12 digits. Now it looks like I have unmatched strings with 11 digits instead of 12.

How can I find all 11 digits strings ONLY. 12 digits of mobile numbers are okay for me, but less than 12 digits are nor correct and I have to find and delete them.

Mofi · Mar 05, 2015#22015-03-05T06:15+00:00

The Perl regular expression search string for this task is \b\d{11}(?!\d)

\b ... word boundary, i.e. beginning of a string consisting of digits in this case.

\d ... any digit.

{11} ... exactly 11 times. Possible would be also {8,11} meaning minimum 8 and maximum 11 times.

(?!\d) ... negative lookahead. The next character after the 11 (or 8 to 11) digits is NOT a digit.

If the file contains just 1 phone number per line and nothing else, you can use for a Perl regular expression Replace All with an empty replace string the search string ^(?:(?!\d{12}).)*$(?:\r?\n|\r) to delete all lines not containing a string with exactly 12 digits. See topic how to delete all lines NOT containing specific word or string or expression?