Regular Expressions 101

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`
(?i)(\s|.)*\bLONG BLOB\b
`
gm
(?i)
match the remainder of the pattern with the following effective flags: gmi
i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])
1st Capturing Group
(\s|.)*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
1st Alternative
\s
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
2nd Alternative
.
. matches any character (except for line terminators)
\b assert position at a word boundary: (^\w|\w$|\W\w|\w\W)
LONG BLOB
matches the characters LONG BLOB literally (case insensitive)
\b assert position at a word boundary: (^\w|\w$|\W\w|\w\W)
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match

`
`
gm

Test String