在mongodb中有$or 操作符的，官网中给出的例子如下：

?

Simple:

db.foo.find( { $or : [ { a : 1 } , { b : 2 } ] } )

With another field

db.foo.find( { name : "bob" , $or : [ { a : 1 } , { b : 2 } ] } )

The?$or?operator retrieves matches for each or clause individually and eliminates duplicates when returning results. A number of?$or?optimizations are planned for 1.8. See?this thread?for details.

$or?cannot be nested.