Text is an unstructured data in which we can extract some entities. Assume that the text is a random sequence of words, punctuation and noise. You can find a really naive text cleaner under the cat.

I forgot the password for the user postgre. I googled about how to recover the password.

There are some java stuff under the cut.

The Boolean search is a model for information retrieval in which Document is considered as a bag of words. Any query is posed as a boolean expression of terms where term means word. Let us consider closely the model by an example.

The majority of a web-applications needs for a search functionality. The easiest way to develop the search functionality in database driven web-applications on their own is using of a regexps. Usually developers remember about that there are a some disadvantages.

• The pattern matching query processes all documents every time and there is no index support.
• There are no liguistic support, eg you are searching for a document that contains entry but documents that contains entries will be missed.
• There is no relevation, ranking, e.t.c.

So why developers use regexps?