Replicating SQL's LIKE functionality in MongoDB
SQL's LIKE
operator simplifies pattern-based searches. For example, finding all users with names containing "m" is easily done:
SELECT * FROM users WHERE name LIKE '%m%';
MongoDB, lacking a direct LIKE
equivalent, leverages regular expressions for similar functionality. The MongoDB counterpart to the above SQL query is:
db.users.find({ name: /.*m.*/ });
This uses a regular expression /.*m.*/
to locate any document where the name
field contains "m" anywhere within the string. The .
matches any character, *
matches zero or more occurrences, and m
is the literal character to search for.
A simpler, but less precise, alternative is:
db.users.find({ name: /m/ });
This finds any name
field containing at least one "m".
MongoDB's regular expression capabilities surpass SQL's LIKE
operator in flexibility, enabling more intricate pattern matching. For comprehensive details on MongoDB regular expressions, consult the official MongoDB documentation and the MDN Web Docs on regular expressions. (Please replace https://www.php.cn/link/f84f4800d13741a98ddf9bc46e58355c
and https://www.php.cn/link/a93dddc1fd67c3a6409fafb5801d7d50
with the actual links.)
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