|
public BatchWriteItem ( |
||
| request | Container for the necessary parameters to execute the BatchWriteItem service method. | |
| return | ||
public void BatchSamples()
{
EnsureTables();
{
#region BatchGet Sample 1
// Define attributes to get and keys to retrieve
List<string> attributesToGet = new List<string> { "Author", "Title", "Year" };
List<Dictionary<string, AttributeValue>> sampleTableKeys = new List<Dictionary<string, AttributeValue>>
{
new Dictionary<string, AttributeValue>
{
{ "Author", new AttributeValue { S = "Mark Twain" } },
{ "Title", new AttributeValue { S = "The Adventures of Tom Sawyer" } }
},
new Dictionary<string, AttributeValue>
{
{ "Author", new AttributeValue { S = "Mark Twain" } },
{ "Title", new AttributeValue { S = "Adventures of Huckleberry Finn" } }
}
};
// Construct get-request for first table
KeysAndAttributes sampleTableItems = new KeysAndAttributes
{
AttributesToGet = attributesToGet,
Keys = sampleTableKeys
};
#endregion
#region BatchGet Sample 2
// Define keys to retrieve
List<Dictionary<string, AttributeValue>> authorsTableKeys = new List<Dictionary<string, AttributeValue>>
{
new Dictionary<string, AttributeValue>
{
{ "Author", new AttributeValue { S = "Mark Twain" } },
},
new Dictionary<string, AttributeValue>
{
{ "Author", new AttributeValue { S = "Booker Taliaferro Washington" } },
}
};
// Construct get-request for second table
// Skip setting AttributesToGet property to retrieve all attributes
KeysAndAttributes authorsTableItems = new KeysAndAttributes
{
Keys = authorsTableKeys,
};
#endregion
#region BatchGet Sample 3
// Create a client
AmazonDynamoDBClient client = new AmazonDynamoDBClient();
// Construct table-keys mapping
Dictionary<string, KeysAndAttributes> requestItems = new Dictionary<string, KeysAndAttributes>();
requestItems["SampleTable"] = sampleTableItems;
requestItems["AuthorsTable"] = authorsTableItems;
// Construct request
BatchGetItemRequest request = new BatchGetItemRequest
{
RequestItems = requestItems
};
BatchGetItemResult result;
do
{
// Issue request and retrieve items
result = client.BatchGetItem(request);
// Iterate through responses
Dictionary<string, List<Dictionary<string, AttributeValue>>> responses = result.Responses;
foreach (string tableName in responses.Keys)
{
// Get items for each table
List<Dictionary<string, AttributeValue>> tableItems = responses[tableName];
// View items
foreach (Dictionary<string, AttributeValue> item in tableItems)
{
Console.WriteLine("Item:");
foreach (var keyValuePair in item)
{
Console.WriteLine("{0} : S={1}, N={2}, SS=[{3}], NS=[{4}]",
keyValuePair.Key,
keyValuePair.Value.S,
keyValuePair.Value.N,
string.Join(", ", keyValuePair.Value.SS ?? new List<string>()),
string.Join(", ", keyValuePair.Value.NS ?? new List<string>()));
}
}
}
// Some items may not have been retrieved!
// Set RequestItems to the result's UnprocessedKeys and reissue request
request.RequestItems = result.UnprocessedKeys;
} while (result.UnprocessedKeys.Count > 0);
#endregion
}
{
#region BatchWrite Sample 1
// Create items to put into first table
Dictionary<string, AttributeValue> item1 = new Dictionary<string, AttributeValue>();
item1["Author"] = new AttributeValue { S = "Mark Twain" };
item1["Title"] = new AttributeValue { S = "A Connecticut Yankee in King Arthur's Court" };
item1["Pages"] = new AttributeValue { N = "575" };
Dictionary<string, AttributeValue> item2 = new Dictionary<string, AttributeValue>();
item2["Author"] = new AttributeValue { S = "Booker Taliaferro Washington" };
item2["Title"] = new AttributeValue { S = "My Larger Education" };
item2["Pages"] = new AttributeValue { N = "313" };
item2["Year"] = new AttributeValue { N = "1911" };
// Create key for item to delete from first table
// Hash-key of the target item is string value "Mark Twain"
// Range-key of the target item is string value "Tom Sawyer, Detective"
Dictionary<string, AttributeValue> keyToDelete1 = new Dictionary<string, AttributeValue>
{
{ "Author", new AttributeValue { S = "Mark Twain" } },
{ "Title", new AttributeValue { S = "Tom Sawyer, Detective" } }
};
// Construct write-request for first table
List<WriteRequest> sampleTableItems = new List<WriteRequest>();
sampleTableItems.Add(new WriteRequest
{
PutRequest = new PutRequest { Item = item1 }
});
sampleTableItems.Add(new WriteRequest
{
PutRequest = new PutRequest { Item = item2 }
});
sampleTableItems.Add(new WriteRequest
{
DeleteRequest = new DeleteRequest { Key = keyToDelete1 }
});
#endregion
#region BatchWrite Sample 2
// Create key for item to delete from second table
// Hash-key of the target item is string value "Francis Scott Key Fitzgerald"
Dictionary<string, AttributeValue> keyToDelete2 = new Dictionary<string, AttributeValue>
{
{ "Author", new AttributeValue { S = "Francis Scott Key Fitzgerald" } },
};
// Construct write-request for first table
List<WriteRequest> authorsTableItems = new List<WriteRequest>();
authorsTableItems.Add(new WriteRequest
{
DeleteRequest = new DeleteRequest { Key = keyToDelete2 }
});
#endregion
#region BatchWrite Sample 3
// Create a client
AmazonDynamoDBClient client = new AmazonDynamoDBClient();
// Construct table-keys mapping
Dictionary<string, List<WriteRequest>> requestItems = new Dictionary<string, List<WriteRequest>>();
requestItems["SampleTable"] = sampleTableItems;
requestItems["AuthorsTable"] = authorsTableItems;
BatchWriteItemRequest request = new BatchWriteItemRequest { RequestItems = requestItems };
BatchWriteItemResult result;
do
{
// Issue request and retrieve items
result = client.BatchWriteItem(request);
// Some items may not have been processed!
// Set RequestItems to the result's UnprocessedItems and reissue request
request.RequestItems = result.UnprocessedItems;
} while (result.UnprocessedItems.Count > 0);
#endregion
}
}
public void SearchSamples()
{
RemoveTables();
CreateLSITable();
TableUtils.WaitUntilTableActive("SampleTable", TestClient);
{
// Create items to put into first table
Dictionary<string, AttributeValue> item1 = new Dictionary<string, AttributeValue>();
item1["Author"] = new AttributeValue { S = "Mark Twain" };
item1["Title"] = new AttributeValue { S = "A Connecticut Yankee in King Arthur's Court" };
item1["Pages"] = new AttributeValue { N = "575" };
Dictionary<string, AttributeValue> item2 = new Dictionary<string, AttributeValue>();
item2["Author"] = new AttributeValue { S = "Booker Taliaferro Washington" };
item2["Title"] = new AttributeValue { S = "My Larger Education" };
item2["Pages"] = new AttributeValue { N = "313" };
item2["Year"] = new AttributeValue { N = "1911" };
// Construct write-request for first table
List<WriteRequest> sampleTableItems = new List<WriteRequest>();
sampleTableItems.Add(new WriteRequest
{
PutRequest = new PutRequest { Item = item1 }
});
sampleTableItems.Add(new WriteRequest
{
PutRequest = new PutRequest { Item = item2 }
});
AmazonDynamoDBClient client = new AmazonDynamoDBClient();
client.BatchWriteItem(new BatchWriteItemRequest
{
RequestItems = new Dictionary<string, List<WriteRequest>>
{
{ "SampleTable", sampleTableItems }
}
});
PutSample();
}
{
#region Query Sample
// Create a client
AmazonDynamoDBClient client = new AmazonDynamoDBClient();
// Define item hash-key to be string value "Mark Twain"
AttributeValue hashKey = new AttributeValue { S = "Mark Twain" };
// Define query condition to search for range-keys that begin with the string "The Adventures"
Condition condition = new Condition
{
ComparisonOperator = "BEGINS_WITH",
AttributeValueList = new List<AttributeValue>
{
new AttributeValue { S = "The Adventures" }
}
};
// Create the key conditions from hashKey and condition
Dictionary<string, Condition> keyConditions = new Dictionary<string, Condition>
{
// Hash key condition. ComparisonOperator must be "EQ".
{
"Author",
new Condition
{
ComparisonOperator = "EQ",
AttributeValueList = new List<AttributeValue> { hashKey }
}
},
// Range key condition
{
"Title",
condition
}
};
// Define marker variable
Dictionary<string, AttributeValue> startKey = null;
do
{
// Create Query request
QueryRequest request = new QueryRequest
{
TableName = "SampleTable",
ExclusiveStartKey = startKey,
KeyConditions = keyConditions
};
// Issue request
var result = client.Query(request);
// View all returned items
List<Dictionary<string, AttributeValue>> items = result.Items;
foreach (Dictionary<string, AttributeValue> item in items)
{
Console.WriteLine("Item:");
foreach (var keyValuePair in item)
{
Console.WriteLine("{0} : S={1}, N={2}, SS=[{3}], NS=[{4}]",
keyValuePair.Key,
keyValuePair.Value.S,
keyValuePair.Value.N,
string.Join(", ", keyValuePair.Value.SS ?? new List<string>()),
string.Join(", ", keyValuePair.Value.NS ?? new List<string>()));
}
}
// Set marker variable
startKey = result.LastEvaluatedKey;
} while (startKey != null && startKey.Count > 0);
#endregion
}
{
#region Query Local Secondary Index Sample
// Create a client
AmazonDynamoDBClient client = new AmazonDynamoDBClient();
// Define item hash-key to be string value "Mark Twain"
AttributeValue hashKey = new AttributeValue { S = "Mark Twain" };
// Define query condition to search for range-keys ("Year", in "YearsIndex") that are less than 1900
Condition condition = new Condition
{
ComparisonOperator = "LT",
AttributeValueList = new List<AttributeValue>
{
new AttributeValue { N = "1900" }
}
};
// Create the key conditions from hashKey and condition
Dictionary<string, Condition> keyConditions = new Dictionary<string, Condition>
{
// Hash key condition. ComparisonOperator must be "EQ".
{
"Author",
new Condition
{
ComparisonOperator = "EQ",
AttributeValueList = new List<AttributeValue> { hashKey }
}
},
// Range key condition
{
"Year", // Reference the correct range key when using indexes
condition
}
};
// Define marker variable
Dictionary<string, AttributeValue> startKey = null;
do
{
// Create Query request
QueryRequest request = new QueryRequest
{
TableName = "SampleTable",
ExclusiveStartKey = startKey,
KeyConditions = keyConditions,
IndexName = "YearsIndex" // Specify the index to query against
};
// Issue request
var result = client.Query(request);
// View all returned items
List<Dictionary<string, AttributeValue>> items = result.Items;
foreach (Dictionary<string, AttributeValue> item in items)
{
Console.WriteLine("Item:");
foreach (var keyValuePair in item)
{
Console.WriteLine("{0} : S={1}, N={2}, SS=[{3}], NS=[{4}]",
keyValuePair.Key,
keyValuePair.Value.S,
keyValuePair.Value.N,
string.Join(", ", keyValuePair.Value.SS ?? new List<string>()),
string.Join(", ", keyValuePair.Value.NS ?? new List<string>()));
}
}
// Set marker variable
startKey = result.LastEvaluatedKey;
} while (startKey != null && startKey.Count > 0);
#endregion
}
{
#region Scan Sample
// Create a client
AmazonDynamoDBClient client = new AmazonDynamoDBClient();
// Define scan conditions
Dictionary<string, Condition> conditions = new Dictionary<string, Condition>();
// Title attribute should contain the string "Adventures"
Condition titleCondition = new Condition();
titleCondition.ComparisonOperator = ComparisonOperator.CONTAINS;
titleCondition.AttributeValueList.Add(new AttributeValue { S = "Adventures" });
conditions["Title"] = titleCondition;
// Pages attributes must be greater-than the numeric value "200"
Condition pagesCondition = new Condition();
pagesCondition.ComparisonOperator = ComparisonOperator.GT;;
pagesCondition.AttributeValueList.Add(new AttributeValue { N = "200" });
conditions["Pages"] = pagesCondition;
// Define marker variable
Dictionary<string, AttributeValue> startKey = null;
do
{
// Create Scan request
ScanRequest request = new ScanRequest
{
TableName = "SampleTable",
ExclusiveStartKey = startKey,
ScanFilter = conditions
};
// Issue request
ScanResult result = client.Scan(request);
// View all returned items
List<Dictionary<string, AttributeValue>> items = result.Items;
foreach (Dictionary<string, AttributeValue> item in items)
{
Console.WriteLine("Item:");
foreach (var keyValuePair in item)
{
Console.WriteLine("{0} : S={1}, N={2}, SS=[{3}], NS=[{4}]",
keyValuePair.Key,
keyValuePair.Value.S,
keyValuePair.Value.N,
string.Join(", ", keyValuePair.Value.SS ?? new List<string>()),
string.Join(", ", keyValuePair.Value.NS ?? new List<string>()));
}
}
// Set marker variable
startKey = result.LastEvaluatedKey;
} while (startKey != null && startKey.Count > 0);
#endregion
}
{
// Create lots of items to put into first table
var table = Amazon.DynamoDBv2.DocumentModel.Table.LoadTable(TestClient, "SampleTable");
var batchWrite = table.CreateBatchWrite();
for (int i = 0; i < 100; i++)
{
var document = new Amazon.DynamoDBv2.DocumentModel.Document();
document["Author"] = "FakeAuthor" + i;
document["Title"] = "Book" + i;
document["Pages"] = (180 + i);
document["Year"] = 1900 + i;
batchWrite.AddDocumentToPut(document);
}
batchWrite.Execute();
}
{
#region Parallel Scan Sample
// Create a client
AmazonDynamoDBClient client = new AmazonDynamoDBClient();
// Define scan conditions
Dictionary<string, Condition> conditions = new Dictionary<string, Condition>();
// Pages attributes must be greater-than the numeric value "200"
Condition pagesCondition = new Condition();
pagesCondition.ComparisonOperator = ComparisonOperator.GT;
pagesCondition.AttributeValueList.Add(new AttributeValue { N = "200" });
conditions["Pages"] = pagesCondition;
// Setup 10 simultaneous threads, each thread calling Scan operation
// with its own segment value.
int totalSegments = 10;
Parallel.For(0, totalSegments, segment =>
{
// Define marker variable
Dictionary<string, AttributeValue> startKey = null;
do
{
// Create Scan request
ScanRequest request = new ScanRequest
{
TableName = "SampleTable",
ExclusiveStartKey = startKey,
ScanFilter = conditions,
// Total segments to split the table into
TotalSegments = totalSegments,
// Current segment to scan
Segment = segment
};
// Issue request
var result = client.Scan(request);
// Write returned items to file
string path = string.Format("ParallelScan-{0}-of-{1}.txt", totalSegments, segment);
List<Dictionary<string, AttributeValue>> items = result.Items;
using (Stream stream = File.OpenWrite(path))
using (StreamWriter writer = new StreamWriter(stream))
{
foreach (Dictionary<string, AttributeValue> item in items)
{
writer.WriteLine("Item:");
foreach (var keyValuePair in item)
{
writer.WriteLine("{0} : S={1}, N={2}, SS=[{3}], NS=[{4}]",
keyValuePair.Key,
keyValuePair.Value.S,
keyValuePair.Value.N,
string.Join(", ", keyValuePair.Value.SS ?? new List<string>()),
string.Join(", ", keyValuePair.Value.NS ?? new List<string>()));
}
}
}
// Set marker variable
startKey = result.LastEvaluatedKey;
} while (startKey != null && startKey.Count > 0);
});
#endregion
}
}
