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 name
FROM country
WHERE 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 name
FROM country
WHERE name REGEXP 'g[o,u]';
Results:
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