You can perform advanced text pattern matching using regular expressions. Regular expressions provide more flexibility than simple wildcard characters in defining rules or views. To match an exact regular expression character, precede the character with a backslash (\).
The following table lists regular expression operators and their definitions:
|
Menu Item |
Character |
Definition |
|---|---|---|
|
Any Character |
. |
Matches any single character. |
|
Character in Range |
[ ] |
Matches any single character from within the bracketed list. Within square brackets, most characters are interpreted literally. |
|
Character Not in Range |
[^] |
Specifies a set of characters not to be matched. |
|
Beginning of Line |
^ |
Matches the beginning of a line. |
|
End of Line |
$ |
Matches the end of a line. |
|
Or |
| |
Matches either the regular expression preceding it or the regular expression following it. |
|
Group |
( ) |
Groups one or more regular expressions to establish a logical regular expression consisting of sub‑regular expressions. Used to override the standard precedence of specific operators. |
|
0 or 1 Matches |
? |
Specifies that the preceding regular expression is matched 0 or 1 time. |
|
0 or More Matches |
* |
Specifies that the preceding regular expression is matched 0 or more times. |
|
1 or More Matches |
+ |
Specifies that the preceding regular expression is matched 1 or more times. |
|
Exactly N Matches |
{n} |
Specifies that the preceding regular expression is matched exactly n number of times. |
|
At Least N Matches |
{n,} |
Specifies that the preceding regular expression is matched n or more times. |
|
At Most N Matches |
{,n} |
Specifies that the preceding regular expression is matched n or fewer times. |
|
N to M Matches |
{n,m} |
Specifies that the preceding regular expression is matched a maximum of m times and a minimum of n times. |
|
New Line Character |
\n |
Matches a new line. |
|
Tab Character |
\t |
Matches a tab character. |
The following table provides examples of regular expressions and matches.
|
Example |
Matches |
Does Not Match |
|---|---|---|
|
st.n |
Austin and Houston |
Webster |
|
st[io]n |
Austin and Houston |
Stanton |
|
st[^io]n |
Stanton |
Houston or Austin |
|
^houston |
Houston |
South Houston or Fort Sam Houston |
|
ston$ |
Houston and Galveston |
Stonewall |
|
dall|hart |
Dallas and Dalhart and Lockhart |
Dale |
|
dal(l|h)art |
Dalhart |
Dallas or Lockhart |
|
il?e$ |
Etoile and Wylie |
Beeville |
|
il*e$ |
Etoile and Wylie and Beeville |
Bellaire |
|
il+e$ |
Etoile and Beeville |
Wylie |
|
ad{2} |
Addison and Caddo |
Adkins |
|
(la.*){2,} |
Highland Village and Lake Dallas |
Laredo |
|
il{,1}e$ |
Bowie and Etoile |
Brownsville |
|
(a.*){2,3} |
Alamo Heights and La Blanca |
Austin or Arkansas Pass |
|
not ville |
Houston and Dallas |
Brownsville |