1.3

LIKE and REGEXP Operators

LIKE and REGEXP Operators

• The LIKE keyword is used with the WHERE clause.
• The LIKE keyword and can use two symbols as wildcards. The percent ( % ) symbol matches any number of characters and the underscore ( _ ) matches a single character
• REGEXP keyword allows you to do more complex pattern matching than a LIKE keyword/
• Some version of REGEXP exists in many computer languages. Refer to the “LIKE and REGEXP” handout for a full list of examples.

Table 2. LIKE Keyword

 LIKE Symbol Description % Match any string of characters to the left of the symbol _ Match a single character

Code Example:

USE world;SELECT nameFROM countryWHERE name LIKE ‘A%’

Results:

Table 3. REXEXP Keyword

 REGEXP Characters Description ^ Match the pattern to the beginning of the value being tested. \$ Match the pattern to the end of the value being tested. . Matches any single character. [charlist] Matches any single character listed within the brackets. [char1 – char2] Matches any single character within the given range. | Separates two string patterns and matches either one

Code Example:

USE world;SELECT nameFROM countryWHERE name REGEXP 'g[o,u]';

Results:

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