Extract a few lines from a large file

I have a large pipe delimited file with approx. 2.3 million rows (records).

I am attempting to locate a particular record.  However I do not have any information regarding the record of interest but I believe that I have information about a record that may be close to it.  So essentially I want to look for the record that I know about, once string is found, I'd like it to write the contents of that line plus a specified number of lines that follows the found string to see if I can identify my missing record.  

 How can I be looking for a record I don't know about?  It is based on counts.  I am missing a single record and based on what was inserted into a database I have pointed the last record that was inserted and I believe the record that is missing should have been inserted after that.

The record that I have information on commences with the following:
D|12345678

The numeric is a unique number.  So I want to be able to get the row where this text appears, output the entire line and print an additional say 3 - 10 lines (or how many lines I desire after) to see if I can locate the missing record.

I have been reading about grep, sed, awk and I am at a total loss how to implement.  I do not want to have to open such a large file and scan to this location in order to find my record.

Any help would be greatly appreciated.