In the previous video, you understood the method and activities for String Manipulation. In this video, you will understand Regular Expressions and the regular expressions builder , Wizard and Studio. So let's get started. Regular Expression or RegEx is a specific search pattern that can be used to easily match, locate and manage text. The studio contains a RegEx builder that simplifies the creation of regular expressions. The RegEx search capabilities and selectors enable the users to identify multiple target elements with a single search execution. RegEx can be used for input validation, string parsing, data scraping, and string manipulation. RegEx can be used for retrieving pieces of texts that follow a certain pattern such as an email address. Now let's learn about the activities which have RegEx builder integrated with them. These are, first, Matches. This activity searches an input string for all occurrences and returns all the successful matches for the given expression. This activity can be used to retrieve all the entries and use them further. Second, IsMatch. This activity indicates whether the specified regular expression finds a match in the specified input string and returns only a true or false value. This activity can serve as a condition for another activity. Third, Replace. This activity replaces strings that match a regular expression pattern with a specified replacement string. This activity can be used for data quality purposes. As you know now about the activities that use the RegEx builder, let's take a look at the RegEx builder wizard. The wizard helps ease the process of building and testing regular expression search criteria. The RegEx wizard can be opened from the body of any of these activities, which are Matches, IsMatch or Replace. Let's drag a Matches activity and click the "Configure Regular Expressions" button to open the RegEx builder. The user interface of the RegEx builder has three sections. They are Test Text, RegEx, Value and Quantifiers, Full Expression. In the test text field, the user can test the chosen search criteria against the text on which RegEx is applied. Before the text editor, the user can choose the RegEx expressions, RegEx value and quantifiers. Doing so highlights the findings in the test text editor. It simplifies building regular expressions by allowing the configuration of RegEx, value and quantifiers. Once a condition is finalized, another one can be added. If there are more than one condition, the order in which they are applied can be configured as well. Let's have a look at RegEx, value and quantifiers. RegEx drop-down allows searching for a given text or one expression from many. It can be configured to search only at the beginning or at the end and also offers pre-built expressions for emails, URLs, US dates or US phone numbers, which are very useful in the case of standardized data. Some examples are Literal, Digit, One of, Not one of, Anything, Any word character, Whitespace, Starts with. The value field contains exactly the texts that needs to be retrieved. The quantifiers drop-down list enables the user to select the type of results that should be displayed. The drop-down has the following options. First, Exactly that selects an exact amount of consecutive occurrences the user wants to find. For example, if the text being searched for is "Hello" and the quantifier is set to exactly two, the wizard finds any occurrences of "Hello, hello" in the test text box. Second, Any (0 or more) that highlights any number of consecutive found matches starting from zero. Third, At least one (1 or more) that highlights any number of consecutive found matches starting from one. Fourth, zero or one that only highlights a single consecutive occurrence of the term. Fifth, Between x and y times that highlights the number of consecutive occurrences selected. For example, searching for "Hello" and selecting between two and three times only highlights "Hello, hello" and "Hello, hello, hello". The Full Expression text box at the bottom of the wizard displays the current RegEx expression in its raw form. And that's it for this video. To understand the string manipulation better you are recommended to go through the next four items in this lesson. Thank you for watching.
