Regex Allow Special Characters


The regex should match ROCKET in upper or lower cases, and with or without punctuation, but not when part of another word. The first entry is the index (starting from 0, of course) where the regular expression matched. js Tagged add methoad in jquery. This query also highlights that spaces are considered special characters, so if we’re interested in all special characters that are not spaces, we can include the space in the not regular expression specification. For example: to match $100 use \$100 - the \$ is taken to mean $. Windows Forms > Windows Forms General. It is used to specify how may times you expect to see the previous character set. But unfortunately, that is not the case. Regular Expression Reference: Special and Non-Printable Characters JGsoft. I need a regular expression in a cold fusion form to allow for all of these special characters: !#$%&'*+-/=?^_`{|}~;. In my app, I allow users to submit urls. Unfortunately the file contains some special characters like german umlauts or null chars, which are escaped with \xDC or \x00. I am struggling to come up with JS that doesn't allow special characters and no spacing on one particular field. Sed format strings. We pass the input, the pattern and the replacement string data. If you only rely on ASCII characters, you can rely on using the hex ranges on the ASCII table. In many cases you can group the regular expression with curly braces, so Tcl pays no attention to it. This only applies to data characters; white space characters may never appear within special character sequences in a pattern. A regular expression can have literal characters in it, and also zero-width positional patterns. Regex to allow anything but whitespace? PHP. Ask Question Asked 4 years, 1 month ago. REGEX password must contain letters a-zA-Z and at least one digit 0-9. Because of this flexibility, user can enter any data and cause the data become dirty. To summarize, the \ o { } form is always safe to use, and the other form is safe to use for code points through \077 when you use exactly three digits to specify them. Pattern), is the main access point of the Java regular expression API. Special Regular Expression Replacement Characters (Literals) % \ < > If you wish to replace any of these characters, they must be preceded by the character to be interpreted as a literal in a replacement. The C++ programming API for using ICU regular expressions is loosely based on the JDK 1. I think this has something to do with Regex but I don't fully understand. This chapter contains the definition of the Shell Command Language. Additionally, it ignores characters in-between and including an un-escaped hash/pound (#) character and the next new line, so that you may include comments in complicated patterns. Regular Expression Reference: Special and Non-Printable Characters JGsoft. This only applies to data characters; white space characters may never appear within special character sequences in a pattern. Here Mudassar Ahmed Khan has explained with an example, how to use Regular Expression (Regex) to accept/allow Alphanumeric characters i. The variable name is case-sensitive. When it comes to password validation using regular expressions, things can get a bit complicated. Help please? Laptop is currently unusable as I am unable to type. * => Matches the preceding character zero or more times. That means ^ and $ anchors. Regular expression help. Matches, Quote. For more information, please refer to Appendix C, "Oracle Regular Expression Support". The following characters are the meta characters that give special meaning to the regular expression search syntax: \ the backslash escape character. A quick reference guide for regular expressions (regex), including symbols, ranges, grouping, assertions and some sample patterns to get you started. * it will match any number of characters. Regular Expression Tutorial Php >>>CLICK HERE<<< This section provides a brief summary of regexp syntax that can be helpful for creating search and issue navigation patterns. The allowed special characters are! But when I test the pattern with a string "test_for_extended_alphanumeric" , the string passes the test. Description : In previous articles I explained constructors in c# , polymorphism example in c# , delegates in c# with example , Difference b/w compile time and runtime polymorphism , sealed classes in c#. In the first two queries, we look for any data row with one special character of an exclamation point [!] and in the next query we look for any special character of an exclamation point in any data row anywhere. NET regex reference. A regular expression defines a search pattern for strings. The jquery-csv parser works on the same fundamental concept except I use regex for terminal/non-terminal tokenization. Regular Expression to Validate the text that contains special characters. See: Terms Used to Describe Apache Directives Digital Signature An encrypted text block that validates a certificate or other file. 03/30/2017; 33 minutes to read +10; In this article. Regular Expression Special Characters \n: Newline \r: Carriage return \t: Tab \0: Null character \YYY: Octal character YYY \xYY: Hexadecimal character YY \x{YY} Hexadecimeal character YY \cY: Control character Y. [0-9a-fA-F]. A regex can also contain groups or ranges of characters, enclosed in square brackets. They can be used to search, edit, or manipulate text and data. regex regex pattern replacement replacement string or pattern start position position in source to begin searching, relative to 1, default is 1 occurrence occurrence of string matching regex pattern, 0=all match i=ignore case, c=case sensitive (additional, less commonly used values allowed as well ). Atleast 1 lower case letter. You might want to set constraints on the length, character set allowed and various other fields in the data input by the user. Try it here! Just type in the text box below. js, add regular expression using jquery. from the regular expression above). Because of this flexibility, user can enter any data and cause the data become dirty. Characters that might indicate line breaks are never treated in any special way when matching character classes, whatever line-ending sequence is in use, and whatever setting of the G_REGEX_DOTALL and G_REGEX_MULTILINE options is used. An example of this is the alphanumeric \w metacharacter which is equivalent to the character range [A-Za-z0-9_] and often used to match characters in English text. Use the `--force-badname' option to relax this check or reconfigure NAME_REGEX. One field is for an address: ^[a-zA-Z0-9]+$ how can I allow spaces and special characters like a comma, number sign and periods. The following HTML Markup consists of a TextBox, a Button and a RegularExpression Validator to which I have applied the Regular Expression (Regex) to accept only Alphabets and Space as valid characters. We can further see this by adding a value to our table with a leading, ending and. This must be an integer value 0 or higher. 1 I require a reqular expression which can accept any character other than single quote('), double quote( ), @, %,# Can anyone help me in this Thanks Regular Expression to exclude some special characters. NET: Use ASP. List of Approved Special Characters ÷ 0247 Division sign ø 0248 Latin small letter o with slash ù 0249 Latin small letter u with grave ú 0250 Latin small letter u with acute û 0251 Latin small letter u with circumflex ü 0252 Latin small letter u with diaeresis ý 0253 Latin small letter y with acute. 121 address and Call User Data to the X. e it allows characters and numbers also,. You can modify this list. A common need when working with strings, even strings from simple console applications, is control. As we’ve seen, a backslash "\" is used to denote character classes. Validation Rule to prevent use of special characters Anyone know how you could create a validation rule on a text field to prevent users from using certain special characters. So it’s a special character in regexps (just like in a regular string). 0 (links to blogs @ MSDN), it stops Powershell style of parsing and allows to feed commands with special characters, without them being treated as such. In the first two queries, we look for any data row with one special character of an exclamation point [!] and in the next query we look for any special character of an exclamation point in any data row anywhere. This is your regex and I added characters as indicated from the second line. The cflags argument is the bitwise-inclusive OR of zero or more of the following flags, which are defined in the header:. Officially, XAMPP's designers intended it for use only as a development tool, to allow website designers and programmers to test their work on their own computers without any access to the Internet. 4 Replies Latest reply on Feb 6, 2003 7:49 PM by 843835. When a string is being created or displayed, its text must be enclosed within double quotation marks to indicate the beginning and end of the string. exactly Make a regex exact Description See exactly. It will also allow for some special characters. This regular expression match can be used for validating strong password. the special characters that are being, or could be, added. The search pattern can be anything from a simple character, a fixed string or a complex expression containing special characters describing the pattern. By the way, most special characters lose their special meaning inside brackets, except for the brackets themselves. regular expression in sublime text 2 to match text. Regular expressions via Wikipedia: A sequence of characters that forms a search pattern, mainly for use in pattern matching with strings, or string matching. I am struggling to come up with JS that doesn't allow special characters and no spacing on one particular field. No special characters or letters allowed. Note: at present, all text submitted to the concordance is internally converted to lower case, so any pattern which searches for an explicit uppercase letter or letters will fail. com is a valid email address. Outside those contexts, or when preceded by a , such a character shall be an ERE that matches the special character itself. identity|id matches id or identity order longer to shorter when alternatives overlap (To match whole words, see scope and groups. loses its special meaning inside a character class, while the expression -becomes a range forming metacharacter. If the regex fails later down the string and needs to backtrack, a regular group containing a quantifier would give up characters one at a time, allowing the engine to try other matches. Please post an example. Unfortunately, I could not think of a quick way to do so on my macbook and I therefore turned to the Internet. hello, My requirement is to validate a field for alphabets and special characters. I have tried to find help about didn't find much. In most of the cases file/folder name are related to the content of the file/folder and starts with number and characters. NET regex tester and complete. Looking for a regular expression to work on a list of comma separated values. Textbox is a search box which can accept names only (a to z and 0-9 only). template bool regex_search (const charT* s, match_results& m, const basic_regex& rgx, regex_constants::match_flag_type flags = regex_constants::match_default); template bool regex_search (const basic_string> Wildcards, Quotes, Back Quotes and Apostrophes in shell commands ( * ? This article deals with 2 issues which are many a times used with each other. Here I show how to use Javascript to allow only numbers to be entered in a textbox. In order to select atoms named Na+, one would use the selection: name "Na\+" In brief, a regular selection allows matching to multiple possibilities, instead of just one character. Single character match. These functions implement the POSIX Extended Regular Expressions (ERE) standard. Re: Special Characters in Teradata There is a function in Teradata named REGEX_SIMILAR that can detect the presence of special characters according to a regular expression. From: bjorn at swift dot st: Assigned: Status: No Feedback: Package: PEAR related: PHP Version: 4. A regular expression is built up of different components, each of which is used to build the regular expression string-generating program. Match anywhere: By default, a regular expression matches a substring anywhere inside the string to be searched. Thanks Venky See if this post helps you any. According to the Java regular expressions API documentation, there is a set of special characters also known as metacharacters present in a regular expression. out how to define 'special characters' in the regex for the. At first, it might look like there is a regular expression character class that would do what I want to do here—that is remove non-alphabetic characters. Re: bug in ^TO_ macro: character '+' *is* allowed in emails, Volker Kuhlmann, 17:50 Re: regex ending in an optional part , Robert Allerstorfer , 17:14 Re: regex ending in an optional part , Dallman Ross , 16:49. Description : In previous articles I explained constructors in c# , polymorphism example in c# , delegates in c# with example , Difference b/w compile time and runtime polymorphism , sealed classes in c#. Such characters typically are not easy to detect (to the human eye) and thus not easily replaceable using the REPLACE T-SQL function. This regular expression can be used for validating a strong password. Extended: This specifies whether to use extended mode for the regular expression. A regular expression is a formalized string of characters that define a pattern. Use the below regex to match names with Capitalization after the first character. PHP Forums on Bytes. Metacharacters are special characters that have a special meaning, such as a wild card character, a repeating character, a nonmatching character, or a range of characters. Of course JavaScript will not prevent determined users from submitting characters you don't want, that needs to be done server-side if it's important, but a JavaScript regex might be good enough. A regular expression, regex or regexp (sometimes called a rational expression) is a sequence of characters that define a search pattern. The regular expression a4% matches the character a followed by a 4 followed by a % sign. Regular expressions via Wikipedia: A sequence of characters that forms a search pattern, mainly for use in pattern matching with strings, or string matching. \n where n is a digit, is expanded to the nth sub-expression. But backslashes already have a special meaning in character strings they are from STAT 133 at University of Guelph. I want to use a Custom validator but no idea what to put in C# code. Of course we can check the basic structure, but this will exclude a large amount of perfectly val. The \G anchor is typically used with the g flag. The regular expression must create a subexpression (backreference) using either the special name FAXNUM (which specifies the destination) or the special name ROUTETO (which specifies the receiver name) or any other backreference name which must match the variable name with which the regular expression is associated. Regular expression calculator supports flags like global match (perform regex action on the whole text instead of the first occurrence), ignore case (case of the provided text will be ignored) and multiline match (perform regex computation across the line boundaries). The latter are text patterns that can help search for strings including email addresses, phone numbers and others with. Recently one of my Twitter followers asked me how they might validate password strength using regular expressions (RegEx) in their code. A regular expression in a programming language is a special text string used for describing a search pattern. Among the chosen few are. Here are some of the more usual ones. It will of course not solve it entirely but would maybe make things easier for some users :) I read about \p{L} but not sure which letters it actually contains and whether there are possible security issues etc. This only applies to data characters; white space characters may never appear within special character sequences in a pattern. There follows some very basic examples of regular expression usage. " and ";" in the TextareaS1 field. We just want to prevent special characters from being used. Regular Expressions Cheat Sheet by DaveChild - Cheatography. hello, My requirement is to validate a field for alphabets and special characters. You can use this control to check whether a user has entered, for example, a valid e-mail address, telephone number, or username or passwo. AND spaces are allowed. There are certain character classes that are so frequently used that a special sequence was created for them. NET regex tester and complete. Regular expression pattern strings may not contain null bytes, but can specify the null byte using the \number notation, e. Simple VBA macro code to remove special characters from a string in excel. A regular expression is a formula for matching strings that have a certain pattern. string-expression [NOT] SIMILAR TO [ESCAPE ] ::= an SQL regular expression ::= a single character Syntax: SQL regular expressions: The following syntax defines the SQL regular expression format. Special Characters URL Encoded Chars. Any character in the alphabet can be used in place of x. Atleast 1 lower case letter. The sequence of the characters is not important. Any character in the alphabet can be used in place of x. To include the dash in a class, you must put it at the beginning or at the end so as not to confuse it with the hyphen that specifies a range of characters [^0-9] Any character except a digit. Bob1 returns valid but should NOT be valid. NET Forums / General ASP. We hope SymbolHound will help programmers find information about their chosen languages and frameworks more easily. Alternatively, if you set the collate flag when constructing the regular expression, then ranges are locale sensitive. This regex should work for any data with a single-character delimiter--just insert the real delimiter in place of each 'X' (and the string you want to exclude in place of "BAD"). We can further see this by adding a value to our table with a leading, ending and. There are certain character classes that are so frequently used that a special sequence was created for them. An ERE special character has special properties in certain contexts. If you wish to match one of these characters literally, place a backslash '\' before it. We handle quoted values. match() This is a reference post for some common RegExp ( regular expressions ) selectors that can be used with the jQuery. Compose Special Characters lets you type two or three characters and use a keyboard shortcut to convert them into a single accented or special character. The simplest regular expression is a single character that matches the same single character in the command output. You can use special character sequences to put non-printable characters in your regular expression. Special Characters. identity|id matches id or identity order longer to shorter when alternatives overlap (To match whole words, see scope and groups. Similarly, the regex cat matches cat in About cats and dogs. A discussion of the character data type in R. using regex in xsd using pattern ltxssimpletype. These patterns are commonly used to ensure the data collected is properly formatted. NET regex tester and complete. Also, - in a character set can mean a range (like "A-Z") so you should either escape it or put it as the very first or very last character (where it couldn't possibly mean a range). You can still take a look, but it. Need help? Post your question and get tips & solutions from a community of 426,495 IT Pros & Developers. Escapes also allow you to specify individual characters that are otherwise hard to type. parameterize a regex Pascal paste special characters split. This generally works fine with regex. By default, regexes are case-sensitive, [a-z] only matches lower cases letters. placing the ^ and $ at beginning and end says 'from the beginning (^) of the string to the end ($) of the string', and the + says '1 or more', so the regex now says 'where the string's contents consist of 1 or more alphanumeric characters spanning from beginng to end of string'. You can modify the regular expressions to allow any minimum or maximum text length, or allow characters other than A–Z. That regex would therefore match any input which starts with a letter, number, underscore or hyphen. Regular Expression Special Characters \n: Newline \r: Carriage return \t: Tab \0: Null character \YYY: Octal character YYY \xYY: Hexadecimal character YY \x{YY} Hexadecimeal character YY \cY: Control character Y. I would like to figure out how to get it to instead interpret those as special New Line characters the same way it does as if I call the function like so:. You should use a live regex tester like liveregex. Meaning all the special characters like period (. Non-Printable Characters. You will have to define what is in this collection of special characters, or conversely that of allowed characters, before you can decide which cases you want to reject. Regex or Regexp, short for regular expressions, is a special string used to define search patterns, typically used on larger texts. The characters you need to type for different characters are listed in the Compose Special Characters dialog (Insert > Compose Character). Available since Powershell v3. Set up your runtime so you can run a pattern and print what it matches easily, for example by running it on a small test text and printing the result of findall(). I am trying to enforce the XSD regular expressions that I find in the SEC's EDGAR schemas, either via Using a regular expression to validate an email address. URL encoding of a character consists of a "%" symbol, followed by the two-digit hexadecimal representation (case-insensitive) of the ISO-Latin code point for the character. A Regular Expression pattern or RegEx pattern is a sequence of characters that is used to validate specific string formats in user input. We can use some comparable expressions to a full regular expression library for matching certain patterns with T-SQL using the like operator. loses its special meaning inside a character class, while the expression -becomes a range forming metacharacter. Introduction to PowerShell Regex – Regular Expression Typical jobs for Regex are to match patterns in text, and to replace individual characters or even whole words. , -and _? What characters will cause problems and shouldn't be allowed in usernames? This is the default NAME_REGEX. Match anywhere: By default, a regular expression matches a substring anywhere inside the string to be searched. Additionally, it ignores characters in-between and including an un-escaped hash/pound (#) character and the next new line, so that you may include comments in complicated patterns. This regular expression will be in used in Java. A character class defines a set of characters, any one of which can occur in an input string for a match to succeed. Invalid preceding regular expression. Need help? Post your question and get tips & solutions from a community of 426,495 IT Pros & Developers. The following regular expression ensures that text is between 1 and 10 characters long, and additionally limits the text to the uppercase letters A–Z. we may want to remove non-printable characters before using the file into the. Example that works (note, this web site form may remove the less than and greater than tags):. However, I have also implemented it to allow the '1' so a number like. I need to validate whether my regex is correct for below scenario. The power of regular expressions comes from the ability to include alternatives and repetitions in the pattern. In a regular expression, putting a set of characters between square brackets makes that part of the expression match any of the characters between the brackets. C# / C Sharp Forums on Bytes. Here Mudassar Ahmed Khan has explained with an example, how to use Regular Expression (Regex) to accept/allow Alphanumeric characters i. The regular expression patterns and behavior are based on Perl's regular expressions. From: bjorn at swift dot st: Assigned: Status: No Feedback: Package: PEAR related: PHP Version: 4. This article will illustrate how to perform AlphaNumeric validation for TextBox i. In one of the columns, I need to check that the entry should not contain any special characters or spaces. Each section in this quick reference lists a particular. Further, immaterial of ddlMethod value, another validation is only alphanumeric characters are allowed at positions 1, 4, 10. Additionally, it ignores characters in-between and including an un-escaped hash/pound (#) character and the next new line, so that you may include comments in complicated patterns. Special Characters. The power of the regular expressions comes when we add special characters to the search string that allow us to more precisely control which lines match the string. Makes sense, thanks. required to facilitate BDT is XML Schema Definition (XSD). abc or 123), then add them to this set. Example that works (note, this web site form may remove the less than and greater than tags):. I have tried to find help about didn't find much. You should use a live regex tester like liveregex. As a result, for most cases, the user does not need to supply any special delimiters for literal strings and/or regular expressions. Active 2 years, 4 months ago. Regex Specification¶ The following characters have special meaning in regular expressions: ^ Matches at beginning of input $ Matches at end of input. For a brief introduction, see. matches("abc", "abc") 2) Character Classes. It returns a boolean that can be used directly as a condition — true if the given string matches the regular expression, false otherwise. The following characters carry special meaning inside "replacement text": $1 to $99 : References the submatched substrings inside parenthesized expressions within the regular expression. I need check that you enter only letters, numbers and special characters ",", ". Regular expressions, regexes for short, are written in a domain-specific language that describes text patterns. If you need a regular expression, you must know if any of the characters of the expression are metacharacters, and must know the right way to quote that character so that it is passed to the program without being modified by the shell. Regular Expression Reference: Special and Non-Printable Characters JGsoft. Some more string manipulations! Today I'd like to remove the special characters and only keep alphanumeric characters using Regular Expression (Regex). Regular Expressions Cheat Sheet from DaveChild. ) The plus sign (+) is used to indicate that consecutive delimiters should be treated as one. The above regular expression matches “alex”. In remarks fields we don't want that user can enter anything, user can only able to enter alphanumeric with white space and some spacial character like -,. Following regex is used in Python to match a string of three numbers, a hyphen, three more numbers, another hyphen, and four numbers. AND the following chars are allowed: " - _ ! ' (double quote, dash, underscore, question, exclamation, single quote) i would very much appriciate a push in the right direction on this (Moderator: Thread Title changed from "regex newbie question" to "Basic Character Matching" for quicker thread understanding during a search). How to replace all blank characters in a String. Allows all characters up to a maximum of 8. i need to implement this inside c# code. Regular Expression can be used in Content Filter conditions. Regular Expressions Cheat Sheet from DaveChild. For more information, please refer to Appendix C, "Oracle Regular Expression Support". This document The following is the UK Postcode Regular Expression and the corresponding detail. please help me on this Regex that allow numbers,question mark and asteriks. hello, My requirement is to validate a field for alphabets and special characters. ^ => It is used to match the beginning of a. For the most part, they are fairly straight forward so this will be a quick rundown on how to use each and any neat features they might have. You can specify individual unicode characters in five ways, either as a variable number of hex digits (four is most common), or by name:. We have seen a wide variety of special symbols such as +, and * and you may wish to match those symbols themselves in a regular expression. A global character pointer _ _loc1 points to where the match began. Compound character classes can help clarify and define sophisticated searches, test for certain conditions. A regular expression is a special sequence of characters that helps you match or find other strings or sets of strings, using a specialized syntax held in a pattern. Boost's ECMAScript grammar allows you to turn this off with regex_constants::no_mod_m. But unfortunately, that is not the case. No special characters or letters allowed. Here is a very useful link which explains which characters are allowed in XML and not allowed in XML. The PowerShell escape character is the grave-accent(`) The escape character can be used in three ways: 1) When used at the end of a line, it is a continuation character - so the command will continue on the next line. match (regex, string) using the regex: "^ [1234]+$". The following regular expression ensures that text is between 1 and 10 characters long, and additionally limits the text to the uppercase letters A-Z. Create a character vector that contains a newline, \n, and parse it using a regular expression. These patterns are used with the exec and test methods of RegExp, and with the match, matchAll, replace, search, and split methods of String. In this case, the asterisk is also known as the Kleene star. All of these characters are allowed in Distinguished Names, but the last three must be escaped. I’ll outline the more commonly used ones, but there are good resources available online that go into more detail. Their associated block has a special syntax (see Synopsis 5). The abbreviation for regular expression is regex. You can remove either all special characters or choose which special characters to remove from the string. Special RegExp Characters. , characters, and words, based on patterns. How to block special characters in a TextBox? ("special characters not allowed"); If we can write a regex expression and validate the keyed entry against, ten. \n where n is a digit, is expanded to the nth sub-expression. ” As soon as you. regex returns NULL on failure or a pointer to the next unmatched character on success. Regular expression to check for specific special characters (any repitition) and 0 to 9 numbers. I need check that you enter only letters, numbers and special characters ",", ". With this example, the strings ab. It includes digits and punctuation and all special characters like $#@!%, etc. Re: bug in ^TO_ macro: character '+' *is* allowed in emails, Volker Kuhlmann, 17:50 Re: regex ending in an optional part , Robert Allerstorfer , 17:14 Re: regex ending in an optional part , Dallman Ross , 16:49. 121 address and Call User Data to the X. Primitive Types: FHIR Name Value Domain XML Representation JSON representation; boolean: true | false: xs:boolean, except that 0 and 1 are not valid values: JSON boolean (true or. from the regular expression above). Should start and end with an alphanumeric character. Expression can include literal. C# program that uses Match, Regex using System; using System. what is the proper syntax in case we need to use special characters in search query, for example: I want to perform search that will return all sharepoint sites that use Team site template - that would mean I need to use # in my search query So, I need a hint about using #, -, _ in my search. Regular Expression Reference Regular expressions play an important role in most text parsing and text matching tasks. Regex Tester isn't optimized for mobile devices yet. NET, Matthew Barnett's alternate regex module for Python and JGSoft (available in RegexBuddy and EditPad). 4 package java. Regular expression calculator supports flags like global match (perform regex action on the whole text instead of the first occurrence), ignore case (case of the provided text will be ignored) and multiline match (perform regex computation across the line boundaries). Special Characters. Allows up to 40 uppercase and lowercase characters and a few special characters that are common to some names. RegularExpressions. Regular expressions allow you to form character classes of words. I also noticed that I had to allow PHP to make 2 characters out of certain special characters (registration symbol) and save it to MySQL as two characters for the decoding to work. do, dog, dg, ads: fog, jog * An asterisk after a character signifies a search for that preceding character repeated 0 or more times. If the token value contains a / character this route won't match. I apply regular expression to accept only characters but it is not accepting space. Of course we can check the basic structure, but this will exclude a large amount of perfectly val. As with LIKE, pattern characters match string characters exactly unless they are special characters in the regular expression language --- but regular expressions use different special characters than LIKE does.