Counters Batch Operation
CounterBatchOperation allows you to operate on multiple counters (Increment
, Get
, Delete
) of different documents in a single request.
Syntax
public CounterBatchOperation(CounterBatch counterBatch)
Parameter | ||
---|---|---|
counterBatch | CounterBatch |
An object that holds a list of DocumentCountersOperation .Each element in the list describes the counter operations to perform for a specific document |
public class CounterBatch
{
public bool ReplyWithAllNodesValues; // A flag that indicates if the results should include a
// dictionary of counter values per database node
public List<DocumentCountersOperation> Documents = new List<DocumentCountersOperation>();
}
DocumentCountersOperation
public class DocumentCountersOperation
{
public string DocumentId; // Id of the document that holds the counters
public List<CounterOperation> Operations; // A list of counter operations to perform
}
CounterOperation
public class CounterOperation
{
public CounterOperationType Type;
public string CounterName;
public long Delta; // the value to increment by
}
CounterOperationType
public enum CounterOperationType
{
Increment,
Delete,
Get
}
Document updates as a result of a counter operation
A document that has counters holds all its counter names in the metadata
.
Therefore, when creating a new counter, the parent document is modified, as the counter's name needs to be added to the metadata.
Deleting a counter also modifies the parent document, as the counter's name needs to be removed from the metadata.
Incrementing an existing counter will not modify the parent document.
Even if a DocumentCountersOperation
contains several CounterOperation
items that affect the document's metadata (create, delete),
the parent document will be modified only once, after all the CounterOperation
items in this DocumentCountersOperation
have been processed.
If DocumentCountersOperation
doesn't contain any CounterOperation
that affects the metadata, the parent document won't be modified.
Return Value
-
CounterBatchOperation returns a
CountersDetail
object, which holds a list ofCounterDetail
objects. -
If a
CounterOperationType
isIncrement
orGet
, aCounterDetail
object will be added to the result.
Delete
operations will not be included in the result.
public class CountersDetail
{
public List<CounterDetail> Counters;
}
public class CounterDetail
{
public string DocumentId; // ID of the document that holds the counter
public string CounterName; // The counter name
public long TotalValue; // Total counter value
public Dictionary<string, long> CounterValues; // A dictionary of counter values per database node
public long Etag; // Counter Etag
public string ChangeVector; // Change vector of the counter
}
Examples
Assume we have two documents, "users/1" and "users/2", that hold 3 counters each -
"likes", "dislikes" and "downloads" - with values 10, 20 and 30 (respectively)
Example #1 : Increment Multiple Counters in a Batch
var operationResult = store.Operations.Send(new CounterBatchOperation(new CounterBatch
{
Documents = new List<DocumentCountersOperation>
{
new DocumentCountersOperation
{
DocumentId = "users/1",
Operations = new List<CounterOperation>
{
new CounterOperation
{
Type = CounterOperationType.Increment,
CounterName = "likes",
Delta = 5
},
new CounterOperation
{
// No Delta specified, value will be incremented by 1
// (From RavenDB 6.2 on, the default Delta is 1)
Type = CounterOperationType.Increment,
CounterName = "dislikes"
}
}
},
new DocumentCountersOperation
{
DocumentId = "users/2",
Operations = new List<CounterOperation>
{
new CounterOperation
{
Type = CounterOperationType.Increment,
CounterName = "likes",
Delta = 100
},
new CounterOperation
{
// this will create a new counter "score", with initial value 50
// "score" will be added to counter-names in "users/2" metadata
Type = CounterOperationType.Increment,
CounterName = "score",
Delta = 50
}
}
}
}
}));
Result:
{
"Counters":
[
{
"DocumentId" : "users/1",
"CounterName" : "likes",
"TotalValue" : 15,
"CounterValues" : null
},
{
"DocumentId" : "users/1",
"CounterName" : "dislikes",
"TotalValue" : 20,
"CounterValues" : null
},
{
"DocumentId" : "users/2",
"CounterName" : "likes",
"TotalValue" : 110,
"CounterValues" : null
},
{
"DocumentId" : "users/2",
"CounterName" : "score",
"TotalValue" : 50,
"CounterValues" : null
}
]
}
Example #2 : Get Multiple Counters in a Batch
var operationResult = store.Operations.Send(new CounterBatchOperation(new CounterBatch
{
Documents = new List<DocumentCountersOperation>
{
new DocumentCountersOperation
{
DocumentId = "users/1",
Operations = new List<CounterOperation>
{
new CounterOperation
{
Type = CounterOperationType.Get,
CounterName = "likes"
},
new CounterOperation
{
Type = CounterOperationType.Get,
CounterName = "downloads"
}
}
},
new DocumentCountersOperation
{
DocumentId = "users/2",
Operations = new List<CounterOperation>
{
new CounterOperation
{
Type = CounterOperationType.Get,
CounterName = "likes"
},
new CounterOperation
{
Type = CounterOperationType.Get,
CounterName = "score"
}
}
}
}
}));
Result:
{
"Counters":
[
{
"DocumentId" : "users/1",
"CounterName" : "likes",
"TotalValue" : 15,
"CounterValues" : null
},
{
"DocumentId" : "users/1",
"CounterName" : "downloads",
"TotalValue" : 30,
"CounterValues" : null
},
{
"DocumentId" : "users/2",
"CounterName" : "likes",
"TotalValue" : 110,
"CounterValues" : null
},
{
"DocumentId" : "users/2",
"CounterName" : "score",
"TotalValue" : 50,
"CounterValues" : null
}
]
}
Example #3 : Delete Multiple Counters in a Batch
var operationResult = store.Operations.Send(new CounterBatchOperation(new CounterBatch
{
Documents = new List<DocumentCountersOperation>
{
new DocumentCountersOperation
{
DocumentId = "users/1",
Operations = new List<CounterOperation>
{
// "likes" and "dislikes" will be removed from counter-names in "users/1" metadata
new CounterOperation
{
Type = CounterOperationType.Delete,
CounterName = "likes"
},
new CounterOperation
{
Type = CounterOperationType.Delete,
CounterName = "dislikes"
}
}
},
new DocumentCountersOperation
{
DocumentId = "users/2",
Operations = new List<CounterOperation>
{
// "downloads" will be removed from counter-names in "users/2" metadata
new CounterOperation
{
Type = CounterOperationType.Delete,
CounterName = "downloads"
}
}
}
}
}));
Result:
{
"Counters": []
}
Example #4 : Mix Different Types of CounterOperations in a Batch
var operationResult = store.Operations.Send(new CounterBatchOperation(new CounterBatch
{
Documents = new List<DocumentCountersOperation>
{
new DocumentCountersOperation
{
DocumentId = "users/1",
Operations = new List<CounterOperation>
{
new CounterOperation
{
Type = CounterOperationType.Increment,
CounterName = "likes",
Delta = 30
},
new CounterOperation
{
// The results will include null for this 'Get'
// since we deleted the "dislikes" counter in the previous example flow
Type = CounterOperationType.Get,
CounterName = "dislikes"
},
new CounterOperation
{
Type = CounterOperationType.Delete,
CounterName = "downloads"
}
}
},
new DocumentCountersOperation
{
DocumentId = "users/2",
Operations = new List<CounterOperation>
{
new CounterOperation
{
Type = CounterOperationType.Get,
CounterName = "likes"
},
new CounterOperation
{
Type = CounterOperationType.Delete,
CounterName = "dislikes"
}
}
}
}
}));
Result:
- Note: The
Delete
operations are Not included in the results.
{
"Counters":
[
{
"DocumentId" : "users/1",
"CounterName" : "likes",
"TotalValue" : 30,
"CounterValues" : null
},
null,
{
"DocumentId" : "users/2",
"CounterName" : "likes",
"TotalValue" : 110,
"CounterValues" : null
}
]
}