Built-in pattern matching provides a versatile tool for making string comparisons. The following table shows the wildcard characters you can use with the Like operator and the number of digits or strings they match.
Character(s) in pattern | Matches in expression |
---|---|
? | Any single character |
* | Zero or more characters |
# | Any single digit (09) |
[charlist] | Any single character in charlist |
[!charlist] | Any single character not in charlist |
A group of one or more characters (charlist) enclosed in brackets ([ ]) can be used to match any single character in expression and can include almost any characters in the ANSI character set, including digits. In fact, the special characters opening bracket ([ ), question mark (?), number sign (#), and asterisk (*) can be used to match themselves directly only if enclosed in brackets. The closing bracket ( ]) can't be used within a group to match itself, but it can be used outside a group as an individual character.
In addition to a simple list of characters enclosed in brackets, charlist can specify a range of characters by using a hyphen (-) to separate the upper and lower bounds of the range. For example, using [A-Z] in pattern results in a match if the corresponding character position in expression contains any of the uppercase letters in the range A through Z. Multiple ranges can be included within the brackets without any delimiting. For example, [a-zA-Z0-9] matches any alphanumeric character.
Other important rules for pattern matching include the following: