Logical Operators
So far, we have learned about various operators used for writing comparison-based queries. The queries we have written so far had only one criterion at a time. But in practical scenarios, you may need to write more complex queries. MongoDB provides four logical operators to help you build logical combinations of multiple criteria in the same query. Let's have a look at them.
$and operator
Using the $and operator, you can have any number of conditions wrapped in an array and the operator will return only the documents that satisfy all the conditions. When a document fails a condition check, the next conditions are skipped. That is why the operator is called a short-circuit operator. For example, say you want to determine the count of unrated movies that were released in 2008. This query must have two conditions:
- The field rated should have a value of
UNRATED - The field year must be equal to
2008
In the document format, both queries can...
