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# Frequently Asked Questions
### Which versions of Apache Cassandra and DSE does the driver support?
The driver supports all Apache Cassandra versions starting from 2.1 and [DataStax Enterprise][dse] versions
from 4.8 to the latest version.
### How do I generate a random uuid or a time-based uuid?
Use the [Uuid and TimeUuid classes](../features/datatypes/uuids) inside the types module.
### Should I create one `Client` instance per module in my application?
Normally you should use one `Client` instance per application. You should share that instance between modules within
your application.
### Should I shut down the pool after executing a query?
No, only call `client.shutdown()` once in your application's lifetime, normally when you shutdown your application.
### How can I use a list of values with the IN operator in a WHERE clause?
To provide a dynamic list of values in a single parameter, use the `IN` operator followed by the question mark
placeholder without parenthesis in the query. The parameter containing the list of values should be of an instance of
Array.
For example:
```javascript
const query = 'SELECT * FROM table1 WHERE key1 = ? AND key2 IN ?';
const key1 = 'param1';
const allKeys2 = [ 'val1', 'val2', 'val3' ];
client.execute(query, [ key1, allKeys2 ], { prepare: true });
```
### Can I use a single `Client` instance for graph and CQL?
Yes, you can. You should use [Execution Profiles](../features/execution-profiles/) to define your settings for CQL and
graph workloads, for example: define which datacenter should be used for graph or for CQL.
[dse]: http://www.datastax.com/products/datastax-enterprise