Anatomy of a search
Search Processing Language (SPL), a special-purpose processing language, was developed to enable fast searching on machine-generated data that has been indexed into Splunk. The language was originally set up to be based on Unix piping and Standard Query Language (SQL). We'll explain piping later. SQL is the language most widely used to query databases. The Search Processing Language (SPL, as opposed to SQL) is a library of all search processing commands and their functions, arguments, and clauses. With a search command you can group different events, filter data based on a constraint, extract fields using regular expressions, perform statistical calculations, and other tasks.
Let us dissect a search query so you can understand exactly how it works. This will also help you to understand what pipes are. As you will see, a pipe basically takes the data that has come from an earlier step and after it has been acted on, filtered, or extracted, sends it on to the next step in...