like operation in mongodb code example

Example 1: how to query mongodb with like

db.users.find({"name": /m/})
or
db.users.find({"name": /.*m.*/})

You're looking for something that contains "m" somewhere
(SQL's '%' operator is equivalent to Regexp's '.*'), 
not something that has "m" anchored to the beginning of the string.

Example 2: like mongodb

db.collection.find( { "url": { "$regex": ".*a.*"} } );