| public AddCondition ( string attributeName, QueryOperator op ) : void | ||
| attributeName | string | Target attribute name |
| op | QueryOperator | Comparison operator |
| Результат | void | |
private static bool TryMatchFieldWithCondition(string fieldName, QueryFilter resultFilter, SearchConditions conditions)
{
List<SearchCondition> conditionList;
if (!conditions.TryGetValue(fieldName, out conditionList))
{
return false;
}
switch (conditionList.Count)
{
case 2: // checking for the between operator
{
var lessThanOrEqualCondition = conditionList.SingleOrDefault(c => c.Operator == ScanOperator.LessThanOrEqual);
var greaterThanOrEqualCondition = conditionList.SingleOrDefault(c => c.Operator == ScanOperator.GreaterThanOrEqual);
if ((lessThanOrEqualCondition == null) || (greaterThanOrEqualCondition == null))
{
throw new InvalidOperationException("Multiple conditions for the same field are only supported for the BETWEEN case");
}
if
(
(lessThanOrEqualCondition.Values.Length != 1)
||
(greaterThanOrEqualCondition.Values.Length != 1)
)
{
return false;
}
resultFilter.AddCondition(fieldName, QueryOperator.Between, greaterThanOrEqualCondition.Values[0], lessThanOrEqualCondition.Values[0]);
}
break;
case 1:
{
SearchCondition condition = conditionList[0];
// here we need to convert operators, as AWS SDK's default conversion is buggy
QueryOperator queryOperator;
if
(
(!TryConvertScanOperatorToQueryOperator(condition.Operator, out queryOperator))
||
(condition.Values.Length != 1)
)
{
return false;
}
resultFilter.AddCondition(fieldName, queryOperator, condition.Values[0]);
}
break;
default:
throw new InvalidOperationException(string.Format("Too many conditions for field {0}", fieldName));
}
// removing the matched condition
conditions.Remove(fieldName);
return true;
}
private Search SearchShards(string sessionId)
{
QueryFilter filter = new QueryFilter();
filter.AddCondition(ATTRIBUTE_SEQUENCE_ID, QueryOperator.GreaterThan, 0);
filter.AddCondition(ATTRIBUTE_SESSION_ID, QueryOperator.Equal, GetHashKey(sessionId));
QueryOperationConfig config = new QueryOperationConfig();
config.AttributesToGet = new List<string> { ATTRIBUTE_SESSION_ID, ATTRIBUTE_SEQUENCE_ID };
config.Select = SelectValues.SpecificAttributes;
config.Filter = filter;
Search search = this._table.Query(config);
return search;
}
/// <summary>
/// Initiates a Search object to Query a DynamoDB table, with the
/// specified hash primary key and filter.
///
/// No calls are made until the Search object is used.
/// </summary>
/// <param name="hashKey">Value of the hash key for the query operation.</param>
/// <param name="filter">Filter to use.</param>
/// <returns>Resultant Search container.</returns>
public Search Query(Primitive hashKey, QueryFilter filter)
{
string hashKeyName = this.HashKeys[0];
QueryFilter fullFilter = new QueryFilter(filter);
fullFilter.AddCondition(hashKeyName, QueryOperator.Equal, hashKey);
return(Query(fullFilter));
}
/// <summary>
/// Initiates a Search object to Query a DynamoDB table, with the
/// specified hash primary key and expression.
///
/// No calls are made until the Search object is used.
/// </summary>
/// <param name="hashKey">Value of the hash key for the query operation.</param>
/// <param name="filterExpression">Expression to use.</param>
/// <returns>Resultant Search container.</returns>
public Search Query(Primitive hashKey, Expression filterExpression)
{
string hashKeyName = this.HashKeys[0];
QueryFilter hashKeyFilter = new QueryFilter();
hashKeyFilter.AddCondition(hashKeyName, QueryOperator.Equal, hashKey);
QueryOperationConfig config = new QueryOperationConfig
{
Filter = hashKeyFilter,
FilterExpression = filterExpression
};
return(Query(config));
}
/// <summary>
/// Initiates a Search object to Query a DynamoDB table, with the
/// specified hash primary key and expression.
///
/// No calls are made until the Search object is used.
/// </summary>
/// <param name="hashKey">Value of the hash key for the query operation.</param>
/// <param name="filterExpression">Expression to use.</param>
/// <returns>Resultant Search container.</returns>
public Search Query(Primitive hashKey, Expression filterExpression)
{
string hashKeyName = this.HashKeys[0];
QueryFilter hashKeyFilter = new QueryFilter();
hashKeyFilter.AddCondition(hashKeyName, QueryOperator.Equal, hashKey);
QueryOperationConfig config = new QueryOperationConfig
{
Filter = hashKeyFilter,
FilterExpression = filterExpression
};
return Query(config);
}
/// <summary>
/// Initiates a Search object to Query a DynamoDB table, with the
/// specified hash primary key and filter.
///
/// No calls are made until the Search object is used.
/// </summary>
/// <param name="hashKey">Value of the hash key for the query operation.</param>
/// <param name="filter">Filter to use.</param>
/// <returns>Resultant Search container.</returns>
public Search Query(Primitive hashKey, QueryFilter filter)
{
string hashKeyName = this.HashKeys[0];
QueryFilter fullFilter = new QueryFilter(filter);
fullFilter.AddCondition(hashKeyName, QueryOperator.Equal, hashKey);
return Query(fullFilter);
}
public static void RunDocumentModelSample()
{
Console.WriteLine("Loading Businesses table");
Table table = Table.LoadTable(client, "Businesses");
Console.WriteLine("Creating and saving first item");
Document chainStore2 = new Document();
chainStore2["Name"] = "Big Sales Inc";
chainStore2["Id"] = 2;
chainStore2["Owner"] = "Big Sales Corp";
chainStore2["Managers"] = new List<string> { "Samantha Jones", "Richard Frost" };
chainStore2["FoundedDate"] = new DateTime(1980, 7, 4);
chainStore2["Address"] = "123 Main Street, New York, New York";
chainStore2["Employees"] = 46;
chainStore2["State"] = "NY";
table.PutItem(chainStore2);
Console.WriteLine("Creating and saving first item");
Document chainStore13 = new Document();
chainStore13["Name"] = "Big Sales Inc";
chainStore13["Id"] = 13;
chainStore13["Owner"] = "Big Sales Corp";
chainStore13["Managers"] = new List<string> { "Anil Garg", "Alex Short" };
chainStore13["FoundedDate"] = new DateTime(1999, 3, 15);
chainStore13["Address"] = "1999 West Ave, Chicago, Illinois";
chainStore13["Employees"] = 54;
chainStore13["State"] = "IL";
table.PutItem(chainStore13);
Console.WriteLine("Creating and saving second item");
Document tinyDiner = new Document();
tinyDiner["Name"] = "Tiny Map-themed Diner";
tinyDiner["Id"] = 0;
tinyDiner["Owner"] = "John Doe";
tinyDiner["FoundedDate"] = new DateTime(1974, 12, 10);
tinyDiner["Address"] = "800 Lincoln Ave, Seattle, Washington";
tinyDiner["State"] = "WA";
table.PutItem(tinyDiner);
Console.WriteLine("Creating and saving third item");
Document internetStore = new Document();
internetStore["Name"] = "Best Online Store Ever";
internetStore["Id"] = 0;
internetStore["Owner"] = "Jane Doe";
internetStore["FoundedDate"] = new DateTime(1994, 2, 19);
internetStore["Employees"] = 5;
internetStore["Url"] = "http://www.best-online-store-ever.fake";
internetStore["Phone"] = "425-555-1234";
table.PutItem(internetStore);
Console.WriteLine("Loading item");
Document doc1 = table.GetItem("Big Sales Inc", 2);
Console.WriteLine("Attribute counts match (should be true): " +
(chainStore2.GetAttributeNames().Count == doc1.GetAttributeNames().Count));
Console.WriteLine("Loading item...");
Document doc2 = table.GetItem("Best Online Store Ever", 0);
Console.WriteLine("Attribute counts match (should be true): " +
(chainStore2.GetAttributeNames().Count == doc1.GetAttributeNames().Count));
Console.WriteLine("Change item: remove one attribute, add one, modify one attribute");
doc2["Phone"] = null;
doc2["Twitter"] = "best-online-store-ever";
doc2["Employees"] = 4;
Console.WriteLine("Updating item");
table.UpdateItem(doc2);
Console.WriteLine("Reloading item");
doc2 = table.GetItem("Best Online Store Ever", 0);
Console.WriteLine("Phone attribute present (should be false): " + doc2.Contains("Phone"));
Console.WriteLine("Twitter attribute present (should be true): " + doc2.Contains("Twitter"));
Console.WriteLine("Employees attribute equals 4: " + (object.Equals(doc2["Employees"].AsPrimitive().Value, "4")));
Console.WriteLine("Loading nonexistent item");
Document doc3 = table.GetItem("Big Sales Inc", 3);
Console.WriteLine("Returned document == null (should be true): " + (doc3 == null));
Search query;
Console.WriteLine();
Console.WriteLine("Querying for items (Equals)");
query = table.Query("Big Sales Inc", new QueryFilter("Id", QueryOperator.Equal, 2));
List<Document> queryItems1 = query.GetRemaining();
Console.WriteLine("Number of items returned (should be 1): " + queryItems1.Count);
Console.WriteLine();
Console.WriteLine("Querying for items (Between)");
QueryFilter filter = new QueryFilter();
filter.AddCondition("Name", QueryOperator.Equal, "Big Sales Inc");
filter.AddCondition("Id", QueryOperator.Between, 0, 15);
QueryOperationConfig queryConfig = new QueryOperationConfig
{
Filter = filter,
Limit = 1
};
query = table.Query(queryConfig);
int totalItems = 0;
while (!query.IsDone)
{
Console.WriteLine("Retrieving next set (page) of items");
List<Document> querySet = query.GetNextSet();
Console.WriteLine("Number of items returned in set (should be 1, unless last set, which will be 0): " + querySet.Count);
foreach (Document doc in querySet)
{
Console.WriteLine("Retrieving individual properties");
Primitive name = doc["Name"].AsPrimitive();
Primitive id = doc["Id"].AsPrimitive();
PrimitiveList managers = doc["Managers"].AsPrimitiveList();
Console.WriteLine("Name = {0}, Id = {1}, # of managers = {2}", name.Value, id.Value, managers.Entries.Count);
totalItems++;
}
}
Console.WriteLine("Total items found (should be 2): " + totalItems);
Search scan;
ScanFilter scanFilter;
Console.WriteLine();
Console.WriteLine("Scanning for items (GreaterThan)");
scanFilter = new ScanFilter();
scanFilter.AddCondition("Employees", ScanOperator.GreaterThan, 50);
scan = table.Scan(scanFilter);
List<Document> scanItems1 = scan.GetRemaining();
Console.WriteLine("Number of items returned (should be 1): " + scanItems1.Count);
Console.WriteLine();
Console.WriteLine("Scanning for items (GreaterThan and LessThan)");
scanFilter = new ScanFilter();
scanFilter.AddCondition("Employees", ScanOperator.GreaterThan, 2);
scanFilter.AddCondition("FoundedDate", ScanOperator.LessThan, new DateTime(1993, 1, 1));
scan = table.Scan(scanFilter);
List<Document> scanItems2 = scan.GetRemaining();
Console.WriteLine("Number of items returned (should be 1): " + scanItems2.Count);
Console.WriteLine();
Console.WriteLine("Retrieving an item");
Document existingDoc = table.GetItem("Big Sales Inc", 13);
Console.WriteLine("Returned document == null (should be false): " + (existingDoc == null));
Console.WriteLine("Deleting item");
table.DeleteItem("Big Sales Inc", 13);
Console.WriteLine("Retrieving same item");
existingDoc = table.GetItem("Big Sales Inc", 13);
Console.WriteLine("Returned document == null (should be true): " + (existingDoc == null));
Console.WriteLine();
Console.WriteLine("Scanning for items (no filter) and deleting all");
scanFilter = new ScanFilter();
scan = table.Scan(scanFilter);
List<Document> scanItems3 = scan.GetRemaining();
Console.WriteLine("Number of items returned (should be 3): " + scanItems3.Count);
for (int i = 0; i < scanItems3.Count; i++)
{
Document item = scanItems3[i];
Console.WriteLine("Deleting item {0} of {1}", i + 1, scanItems3.Count);
table.DeleteItem(item);
}
Console.WriteLine("Scanning table again");
scan = table.Scan(scanFilter);
scanItems3 = scan.GetRemaining();
Console.WriteLine("Number of items returned (should be 0): " + scanItems3.Count);
}
