update $and

Author: kay-kim

source/reference/operator/query/and.txt

@@ -25,9 +25,7 @@ $and
    .. note::
 
       MongoDB provides an implicit ``AND`` operation when specifying a
-      comma separated list of expressions.  Using an explicit ``AND``
-      with the :query:`$and` operator is necessary when the same field
-      or operator has to be specified in multiple expressions.
+      comma separated list of expressions.
 
 Examples
 --------
@@ -63,17 +61,17 @@ Consider the following example:
 .. code-block:: javascript
 
    db.inventory.find( {
-       $and : [
-           { $or : [ { price : 0.99 }, { price : 1.99 } ] },
-           { $or : [ { sale : true }, { qty : { $lt : 20 } } ] }
+       $and: [
+           { $or: [ { qty: { $lt : 10 } }, { qty : { $gt: 50 } } ] },
+           { $or: [ { sale: true }, { price : { $lt : 5 } } ] }
        ]
    } )
 
 This query will select all documents where:
 
-- the ``price`` field value equals ``0.99`` or ``1.99``, **and**
-- the ``sale`` field value is equal to ``true`` **or** the ``qty``
-  field value is less than ``20``.
+- the ``qty`` field value is less than ``20`` or greater than ``50``, **and**
+- the ``sale`` field value is equal to ``true`` **or** the ``price``
+  field value is less than ``5``.
 
 This query cannot be constructed using an implicit ``AND`` operation,
 because it uses the :query:`$or` operator more than once.