The like and not like have two search symbols. The underscore _ character that looks for one character and the percentage % character that looks for zero or more characters. I use function  table which has function_name,  function_name and function_description fields. Lets see the example:

SELECT *
FROM `functions`
WHERE function_name LIKE 'a%'
LIMIT 0 , 30

Above query will only pick out result that provide a TRUE result according to the WHERE equation. We can see that equation will equal the LIKE value plus some possible extra characters afterwards.

The LIKE search is not case sensitive, so it will accept anything starting with ‘a’ as well.

So how LIKE search can make a different lowercase or uppercase letters? by adding BINARY word after LIKE.

SELECT *
FROM `functions`
WHERE function_name LIKE BINARY "a%"
LIMIT 0 , 30;

And the change the query like below to see the different:

SELECT *
FROM `functions`
WHERE function_name LIKE BINARY "A%"
LIMIT 0 , 30;

Queries using the LIKE or NOT LIKE parameters may be a bit slower than a normal query search considering they are a broader value and do not take advantage of any indexing.

Note: If you want to have an underscore or percentage character actually be part of the search value, put an escape slash \ in front of the character.

The underscore wildcard can be used a number of times to find a specific number of characters. Example, this would be used in an equation to return a value of ‘Stan’ plus 3 characters.

SELECT *
FROM `functions`
WHERE function_name LIKE BINARY "mdat___"
LIMIT 0 , 30;

The underscore and percentage characters (also known as wildcard) can be used in front, at the end, or both ends of a value.