Wildcards

The “=” operator is used to find exact matches for text fields, including capitalisation:

WHERE surname = 'Johnson'

The LIKE operator can also be used to find exact matchs, but capitalisation is ignored:

WHERE surname LIKE 'johnson'

The main purpose of the LIKE operator is to allow use of wildcards, where only parts of the string pattern are specified.

SQL MS Access
&
*
matches zero, one or many characters
_
?
matches a single character

Examples:

-- Match surnames that start with 'Thom'
WHERE surname LIKE 'Thom%'
-- Match surnames that end with 'son'
WHERE surname LIKE '%son'
-- Match surnames that start with 'Thom' and end with 'son'
WHERE surname LIKE 'Thom%son'
-- Match surnames contain 'is' anywhere
WHERE surname LIKE '%is%'
-- Match surnames that have 'H' as the second letter
WHERE surname LIKE '_h%'
-- Match surnames that start with ;m; and have at least three characters
WHERE surname LIKE 'm_%_%'