public Results Query(Transaction txn, string query, QueryContext context)
{
return Results.Create(this.mgr_.query(Transaction.ToInternal(txn), query, QueryContext.ToInternal(context)));
}
public Results Query(Transaction txn, string query, QueryContext context, DocumentConfig config)
{
return Results.Create(this.mgr_.query(Transaction.ToInternal(txn), query, QueryContext.ToInternal(context), config.Flags));
}
private static string getNewDocument(Manager mgr, Document document,
QueryContext context, string docString)
{
// Get the substring that we want to replace
string inventory = getValue(mgr, document,
"/*/inventory/inventory/text()", context);
// Convert the String representation of the inventory level to an
// integer, increment by 1, and then convert back to a String for
// replacement on the document.
int newInventory = System.Int32.Parse(inventory) + 1;
string newVal = newInventory.ToString();
// Perform the replace
StringBuilder strbuff = new StringBuilder(docString);
strbuff.Replace(inventory, newVal);
System.Console.WriteLine("Inventory was " + inventory +
", it is now " + newVal + ".");
return strbuff.ToString();
}
public QueryExpression Prepare(Transaction txn, string query, QueryContext context)
{
return QueryExpression.Create(this.mgr_.prepare(Transaction.ToInternal(txn), query, QueryContext.ToInternal(context)));
}
// Method that deletes all documents from a DB XML container that match a given
// XQuery.
private static void doDeleteDocument(Manager mgr, Container container,
string query, QueryContext context, Transaction txn)
{
System.Console.WriteLine("Deleting documents for expression: '" + query + "'.");
System.Console.WriteLine("Return to continue: ");
System.Console.ReadLine();
// Perform our query. We'll delete any document contained in this result set.
Results results = mgr.Query(txn, query, context, new DocumentConfig());
System.Console.WriteLine("Found " + results.Size +
" matching the expression '" + query + "'.");
// Get an update context.
using(UpdateContext updateContext = mgr.CreateUpdateContext())
{
while(results.MoveNext())
{
Document document = results.Current.ToDocument();
string name = document.Name;
System.Console.WriteLine("Deleting document: " + name + ".");
// Peform the delete
container.DeleteDocument(txn, document, updateContext);
System.Console.WriteLine("Deleted document: " + name + ".");
}
}
}
// Modifies an XML document that is stored in a DB XML container
private static void doUpdateDocument(Manager mgr, Container container,
string query, QueryContext context, Transaction txn)
{
System.Console.WriteLine("Updating documents for expression: '" + query + "'.");
System.Console.WriteLine("Return to continue: ");
System.Console.ReadLine();
// query for all the documents that we want to update
Results results = mgr.Query(txn, query, context, new DocumentConfig());
System.Console.WriteLine("Found " + results.Size +
" matching the expression '" + query + "'.");
// Get an update context.
using(UpdateContext updateContext = mgr.CreateUpdateContext())
{
while(results.MoveNext())
{
Document document = results.Current.ToDocument();
// Retrieve the entire document as a single String object
string docString = document.StringContent;
System.Console.WriteLine("Updating document: ");
System.Console.WriteLine(docString);
// This next method just modifies the document string
// in a small way.
string newDocString = getNewDocument(mgr, document, context,
docString);
System.Console.WriteLine("Updating document...");
//Set the document's content to be the new document string
document.StringContent = newDocString;
// Now replace the document in the container
container.UpdateDocument(txn, document, updateContext);
System.Console.WriteLine("Document updated.");
}
}
}
public Results LookupIndex(Transaction txn, QueryContext context, IndexSpecification.Entry entry)
{
return this.LookupIndex(txn, context, entry, null, new DocumentConfig());
}
// Performs a query against a document using an QueryContext.
private static void doContextQuery(Manager mgr, string query,
QueryContext context)
{
// Perform a single query against the referenced container using
// the referenced context.
System.Console.WriteLine("Exercising query: '" + query + "'.");
System.Console.WriteLine("Return to continue: ");
System.Console.ReadLine();
// Perform the query
Results results = mgr.Query(null, query, context, new DocumentConfig());
// Iterate over the results
while(results.MoveNext())
{
System.Console.WriteLine(results.Current);
}
System.Console.WriteLine(results.Size + " results returned for query '"
+ query + "'.");
}
// Method to add a "description" element after the query's target nodes
private static void doModify(Manager mgr, Container container, QueryContext context,
string query, Transaction txn)
{
using(QueryExpression expression = mgr.Prepare(txn, query, context))
{
System.Console.WriteLine("Updating document for the expression: '" +
query + "' ");
System.Console.WriteLine("Return to continue: ");
System.Console.ReadLine();
// Print the document(s) to be updated -- those that describe
// Zapote Blanco (a fruit). The document strings are only being
// printed to show before/after results.
// Most modification programs would not perform the additional queries.
using(Results results = expression.Execute(txn, context, new DocumentConfig()))
{
dumpDocuments(results);
results.Reset();
System.Console.WriteLine("About to update the document(s) above.");
System.Console.WriteLine("Look for a new element after the target " +
"element, named 'description' ...");
System.Console.WriteLine("Return to continue: ");
System.Console.ReadLine();
// The modification is a new element in the target node, called
// "descripton, which goes immediately after the <product> element.
// if this program is run more than once, and committed, additional
// identical elements are added. It is easy to modify this program
// to change the modification.
using(Modify modify = mgr.CreateModify())
{
using(QueryExpression subexpr = mgr.Prepare(txn, ".", context))
{
modify.AddInsertAfterStep(subexpr, Modify.XmlObject.Element, "description", "very nice");
using(UpdateContext uc = mgr.CreateUpdateContext())
{
long numMod = modify.Execute(txn, results, context, uc);
System.Console.WriteLine("Performed " + numMod + " modification operations");
dumpDocuments(results);
}
}
}
}
}
}
// Shows a timestamp for each record that matches the given XPath query.
// The timestamp is stored as metadata on each document. This metadata was
// added to the document when the example data was loaded into the container
// using exampleLoadContainer.java. The timestamp represents the time
// when the document was loaded into the container.
private static void showTimeStamp(Manager mgr, string query,
QueryContext context)
{
// Perform a single query against the referenced container using
// the referenced context. The timestamp metadata attribute is then
// displayed.
System.Console.WriteLine("Exercising query: '" + query + "'.");
System.Console.WriteLine("Return to continue: ");
System.Console.ReadLine();
//Perform the query
Results results = mgr.Query(null, query, context, new DocumentConfig());
while(results.MoveNext())
{
using(Document document = results.Current.ToDocument())
{
// We return the metadata as a MetaData object
using(MetaData md = document.GetMetaData("http://dbxmlExamples/timestamp", "timeStamp"))
{
System.Console.WriteLine("Document " + document.Name +
" stored on " + md.Value.ToDateTime());
}
}
}
System.Console.WriteLine(results.Size + " results returned for query '"
+ query + "'.");
}
public Results Execute(Transaction txn, Value contextItem, QueryContext context, DocumentConfig config)
{
return Results.Create(this.qe_.execute(Transaction.ToInternal(txn), Value.ToInternal(contextItem), QueryContext.ToInternal(context), config.Flags));
}
internal static XmlQueryContext ToInternal(QueryContext v)
{
if (v == null)
{
return null;
}
return v.Internal;
}
public int Execute(Transaction txn, Value toModify, QueryContext context, UpdateContext uc)
{
return((int)this.mod_.execute(Transaction.ToInternal(txn), Value.ToInternal(toModify), QueryContext.ToInternal(context), UpdateContext.ToInternal(uc)));
}
private static string getValue(Manager mgr, Document document,
string query, QueryContext context)
{
///////////////////////////////////////////////////////////////////////////
//////// Return specific information from a document. //////////////////
//////// Assumes a result set of size 1 //////////////////
///////////////////////////////////////////////////////////////////////////
using(Value docValue = new Value(document))
{
// Perform the query
// The document provides the context for the query, so neither
// collection() nor doc() needs to be part of the query.
using(QueryExpression queryExpr = mgr.Prepare(null, query, context))
{
using(Results result = queryExpr.Execute(null, docValue, context, new DocumentConfig()))
{
// We require a result set size of 1.
if(!result.MoveNext())
{
System.Console.WriteLine("Error! query '" + query +
"' returned a result size size != 1");
throw new System.Exception( "getValue found result set not equal to 1.");
}
// Get the value. If we allowed the result set to be larger than size 1,
// we would have to loop through the results, processing each as is
// required by our application.
return result.Current.ToString();
}
}
}
}
public Results LookupIndex(Transaction txn, QueryContext context, IndexSpecification.Entry entry, string parent_uri, string parent_name, Value value)
{
return this.LookupIndex(txn, context, entry, parent_uri, parent_name, value, new DocumentConfig());
}
private static void getDetails(Manager mgr, string query, QueryContext context)
{
// Perform a single query against the referenced container using
// the referenced context.
System.Console.WriteLine("Exercising query: '" + query + "'.");
System.Console.WriteLine("Return to continue:");
System.Console.ReadLine();
// Perform the query
Results results = mgr.Query(null, query, context, new DocumentConfig());
System.Console.WriteLine("\tProduct : Price : Inventory Level");
while(results.MoveNext())
{
/// Retrieve the value as a document
using(Document theDocument = results.Current.ToDocument())
{
// Obtain information of interest from the document. Note that the
// wildcard in the query expression allows us to not worry about what
// namespace this document uses.
string item = getValue(mgr, theDocument,
"string(/*/product)", context);
string price = getValue(mgr, theDocument,
"string(/*/inventory/price)", context);
string inventory = getValue(mgr, theDocument,
"string(/*/inventory/inventory)", context);
System.Console.WriteLine("\t" + item + " : " + price + " : " +
inventory);
}
}
System.Console.WriteLine(results.Size + " results returned for query '" +
query + "'.");
}
public Results LookupIndex(Transaction txn, QueryContext context, IndexSpecification.Entry entry, string parent_uri, string parent_name, Value value, DocumentConfig config)
{
return Results.Create(this.cont_.lookupIndex(Transaction.ToInternal(txn), QueryContext.ToInternal(context), entry.URI, entry.Name, parent_uri, parent_name, entry.Index, Value.ToInternal(value), config.Flags));
}
public int Execute(Transaction txn, Value toModify, QueryContext context, UpdateContext uc)
{
return (int) this.mod_.execute(Transaction.ToInternal(txn), Value.ToInternal(toModify), QueryContext.ToInternal(context), UpdateContext.ToInternal(uc));
}
// Utility method that we use to make sure the documents that we thought
// were deleted from the container are in fact deleted.
private static void confirmDelete(Manager mgr, string query, QueryContext context)
{
System.Console.WriteLine("Confirming the delete.");
System.Console.WriteLine("The query: '" + query +
"' should return result set size 0.");
Results results = mgr.Query(null, query, context, new DocumentConfig());
if(results.Size == 0)
{
System.Console.WriteLine("Result set size is 0. Deletion confirmed.");
}
else
{
System.Console.WriteLine("Result set size is " + results.Size +
". Deletion failed.");
}
}
