![]() ![]() For example, it would return a value such as 'Hello%'. This MySQL LIKE condition example returns all suppliers whose name starts with H and ends in the literal %. WHERE supplier_name LIKE 'H%!%' ESCAPE '!' We could modify this LIKE condition by specfying an escape character as follows: SELECT * Since we did not specify an escape character in the LIKE condition, MySQL assumes that the escape character is "\" which results in MySQL treating the second % character as a literal instead of a wildcard. This MySQL LIKE condition example returns all suppliers whose name starts with H and ends in %. Here is another more complicated example using escape characters in the MySQL LIKE condition. As a result, this statement will also return all suppliers whose supplier_name is G%. The ! escape character would result in MySQL treating the % character as a literal. This MySQL LIKE condition example identifies the ! character as an escape character. WHERE supplier_name LIKE 'G!%' ESCAPE '!' We can override the default escape character in MySQL by providing the ESCAPE modifier as follows: SELECT * This statement would then return all suppliers whose supplier_name is G%. MySQL then assumes that the escape character is "\" which results in MySQL treating the % character as a literal instead of a wildcard. Since we didn't specify an escape character, MySQL assumes that the "\" is the escape character. Please note that you can only define an escape character as a single character (length of 1). You can do this using an Escape character. Let's say you wanted to search for a % or a _ character in the MySQL LIKE condition. These examples deal specifically with escaping characters in MySQL. It is important to understand how to "Escape Characters" when pattern matching. The example above, would retrieve potentially 10 records back (where the missing value could equal anything from 0 to 9). You might find that you are looking for an account number, but you only have 5 of the 6 digits. For example, it could return suppliers whose supplier_name is 'Smith', 'Smyth', 'Smath', 'Smeth', etc. This MySQL LIKE condition example would return all suppliers whose supplier_name is 5 characters long, where the first two characters are 'Sm' and the last two characters are 'th'. Remember that _ wildcard is looking for only one character. Next, let's explain how the _ wildcard (underscore wildcard) works in the MySQL LIKE condition. ![]() If you choose to use the “\” character as part of your pattern in a regular expression it will need to escaped with another backslash “\\”.įor further documentation on the MySQL regular expression operator, please visit Regular Expressions in the MySQL Reference Manual (v5.1 currently linked).Example - Using _ wildcard (underscore wildcard) * NOTE: MySQL interprets the “\” (backslash) character as an escape character. ![]() ] : These markers stand for word boundaries, and as such they match the beginning and ending of words, respectively.the pattern ] would match against a string that is all aphabetic characters. : Within a bracket expression, represents a character class that matches all characters belonging to that class.It matches all characters with the same collation value, including itself. : Within a bracket expression, represents an equivalence class.the pattern ] would match the ‘.’ (period) character. : Within a bracket expression (using “”), matches the sequence of characters of that collating element.A “-” character between two other characters forms a range that maches all characters from the first character to the second. , : Matches any character that is (or is not, if ^ is used) either a, b, c, d, or X.( abc)* : Match zero or more instances of the character sequence abc.de| abc : Match either of the character sequences, de or abc. ![]()
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