(PECL mongo >=0.8.1)
This class can be used to create regular expressions. Typically, these expressions will be used to query the database and find matching strings. More unusually, they can be saved to the database and retrieved.
Mongo recognizes six regular expression flags:
i
Case insensitive
m
Multiline
x
Can contain comments
l
locale
s
dotall, "." matches everything, including newlines
u
match unicode