private void DiagnoseKeyCollision(UpdateCompiler compiler, PropagatorResult change, CompositeKey key, PropagatorResult other)
{
KeyManager keyManager = compiler.m_translator.KeyManager;
CompositeKey otherKey = new CompositeKey(GetKeyConstants(other));
// determine if the conflict is due to shared principal key values
bool sharedPrincipal = true;
for (int i = 0; sharedPrincipal && i < key.KeyComponents.Length; i++)
{
int identifier1 = key.KeyComponents[i].Identifier;
int identifier2 = otherKey.KeyComponents[i].Identifier;
if (!keyManager.GetPrincipals(identifier1).Intersect(keyManager.GetPrincipals(identifier2)).Any())
{
sharedPrincipal = false;
}
}
if (sharedPrincipal)
{
// if the duplication is due to shared principals, there is a duplicate key exception
var stateEntries = SourceInterpreter.GetAllStateEntries(change, compiler.m_translator, m_table)
.Concat(SourceInterpreter.GetAllStateEntries(other, compiler.m_translator, m_table));
throw EntityUtil.Update(Strings.Update_DuplicateKeys, null, stateEntries);
}
else
{
// if there are no shared principals, it implies that common dependents are the problem
HashSet <IEntityStateEntry> commonDependents = null;
foreach (PropagatorResult keyValue in key.KeyComponents.Concat(otherKey.KeyComponents))
{
var dependents = new HashSet <IEntityStateEntry>();
foreach (int dependentId in keyManager.GetDependents(keyValue.Identifier))
{
PropagatorResult dependentResult;
if (keyManager.TryGetIdentifierOwner(dependentId, out dependentResult) &&
null != dependentResult.StateEntry)
{
dependents.Add(dependentResult.StateEntry);
}
}
if (null == commonDependents)
{
commonDependents = new HashSet <IEntityStateEntry>(dependents);
}
else
{
commonDependents.IntersectWith(dependents);
}
}
// to ensure the exception shape is consistent with constraint violations discovered while processing
// commands (a more conventional scenario in which different tables are contributing principal values)
// wrap a DataConstraintException in an UpdateException
throw EntityUtil.Update(Strings.Update_GeneralExecutionException,
EntityUtil.Constraint(Strings.Update_ReferentialConstraintIntegrityViolation), commonDependents);
}
}
/// <summary>
/// Builds an update command.
/// </summary>
/// <param name="oldRow">Old value of the row being updated.</param>
/// <param name="newRow">New value for the row being updated.</param>
/// <param name="processor">Context for the table containing row.</param>
/// <returns>Update command.</returns>
internal UpdateCommand BuildUpdateCommand(PropagatorResult oldRow,
PropagatorResult newRow, TableChangeProcessor processor)
{
// If we're updating a row, the row may not need to be touched (e.g., no concurrency validation required)
bool rowMustBeTouched = false;
DbExpressionBinding target = GetTarget(processor);
// Create set clauses and returning parameter
Dictionary <int, string> outputIdentifiers;
DbExpression returning;
List <DbModificationClause> setClauses = new List <DbModificationClause>();
foreach (DbModificationClause clause in BuildSetClauses(
target, newRow, oldRow, processor, /* insertMode */ false, out outputIdentifiers, out returning,
ref rowMustBeTouched))
{
setClauses.Add(clause);
}
// Construct predicate identifying the row to modify
DbExpression predicate = BuildPredicate(target, oldRow, newRow, processor, ref rowMustBeTouched);
if (0 == setClauses.Count)
{
if (rowMustBeTouched)
{
List <IEntityStateEntry> stateEntries = new List <IEntityStateEntry>();
stateEntries.AddRange(SourceInterpreter.GetAllStateEntries(
oldRow, m_translator, processor.Table));
stateEntries.AddRange(SourceInterpreter.GetAllStateEntries(
newRow, m_translator, processor.Table));
if (stateEntries.All(it => (it.State == EntityState.Unchanged)))
{
rowMustBeTouched = false;
}
}
// Determine if there is nothing to do (i.e., no values to set,
// no computed columns, and no concurrency validation required)
if (!rowMustBeTouched)
{
return(null);
}
}
// Initialize DML command tree
DbUpdateCommandTree commandTree =
new DbUpdateCommandTree(m_translator.MetadataWorkspace, DataSpace.SSpace, target, predicate, setClauses.AsReadOnly(), returning);
// Create command
UpdateCommand command = new DynamicUpdateCommand(processor, m_translator, ModificationOperator.Update, oldRow, newRow, commandTree, outputIdentifiers);
return(command);
}
/// <summary>
/// Finds all markup associated with the given source.
/// </summary>
/// <param name="source">Source expression. Must not be null.</param>
/// <param name="translator">Translator containing session information.</param>
/// <param name="sourceTable">Table from which the exception was thrown (must not be null).</param>
/// <returns>Markup.</returns>
internal static ReadOnlyCollection<IEntityStateEntry> GetAllStateEntries(PropagatorResult source, UpdateTranslator translator,
EntitySet sourceTable)
{
Debug.Assert(null != source);
Debug.Assert(null != translator);
Debug.Assert(null != sourceTable);
SourceInterpreter interpreter = new SourceInterpreter(translator, sourceTable);
interpreter.RetrieveResultMarkup(source);
return new ReadOnlyCollection<IEntityStateEntry>(interpreter.m_stateEntries);
}
/// <summary>
/// Finds all markup associated with the given source.
/// </summary>
/// <param name="source">Source expression. Must not be null.</param>
/// <param name="translator">Translator containing session information.</param>
/// <param name="sourceTable">Table from which the exception was thrown (must not be null).</param>
/// <returns>Markup.</returns>
internal static ReadOnlyCollection <IEntityStateEntry> GetAllStateEntries(PropagatorResult source, UpdateTranslator translator,
EntitySet sourceTable)
{
Debug.Assert(null != source);
Debug.Assert(null != translator);
Debug.Assert(null != sourceTable);
SourceInterpreter interpreter = new SourceInterpreter(translator, sourceTable);
interpreter.RetrieveResultMarkup(source);
return(new ReadOnlyCollection <IEntityStateEntry>(interpreter.m_stateEntries));
}
internal override IList <IEntityStateEntry> GetStateEntries(UpdateTranslator translator)
{
List <IEntityStateEntry> stateEntries = new List <IEntityStateEntry>(2);
if (null != this.OriginalValues)
{
foreach (IEntityStateEntry stateEntry in SourceInterpreter.GetAllStateEntries(
this.OriginalValues, translator, this.Table))
{
stateEntries.Add(stateEntry);
}
}
if (null != this.CurrentValues)
{
foreach (IEntityStateEntry stateEntry in SourceInterpreter.GetAllStateEntries(
this.CurrentValues, translator, this.Table))
{
stateEntries.Add(stateEntry);
}
}
return(stateEntries);
}
/// <summary>
/// Propagate all changes associated with a particular join key.
/// </summary>
/// <param name="key">Key.</param>
/// <param name="result">Resulting changes are added to this result.</param>
private void Propagate(CompositeKey key, ChangeNode result, JoinDictionary leftDeletes, JoinDictionary leftInserts,
JoinDictionary rightDeletes, JoinDictionary rightInserts)
{
// Retrieve changes associates with this join key
Tuple <CompositeKey, PropagatorResult> leftInsert = null;
Tuple <CompositeKey, PropagatorResult> leftDelete = null;
Tuple <CompositeKey, PropagatorResult> rightInsert = null;
Tuple <CompositeKey, PropagatorResult> rightDelete = null;
Ops input = Ops.Nothing;
if (leftInserts.TryGetValue(key, out leftInsert))
{
input |= Ops.LeftInsert;
}
if (leftDeletes.TryGetValue(key, out leftDelete))
{
input |= Ops.LeftDelete;
}
if (rightInserts.TryGetValue(key, out rightInsert))
{
input |= Ops.RightInsert;
}
if (rightDeletes.TryGetValue(key, out rightDelete))
{
input |= Ops.RightDelete;
}
// Get propagation rules for the changes
Ops insertRule = m_insertRules[input];
Ops deleteRule = m_deleteRules[input];
if (Ops.Unsupported == insertRule || Ops.Unsupported == deleteRule)
{
// If no propagation rules are defined, it suggests an invalid workload (e.g.
// a required entity or relationship is missing). In general, such exceptions
// should be caught by the RelationshipConstraintValidator, but we defensively
// check for problems here regardless. For instance, a 0..1:1..1 self-assocation
// implied a stronger constraint that cannot be checked by RelationshipConstraintValidator.
// First gather state entries contributing to the problem
List <IEntityStateEntry> stateEntries = new List <IEntityStateEntry>();
Action <Tuple <CompositeKey, PropagatorResult> > addStateEntries = (r) =>
{
if (r != null)
{
stateEntries.AddRange(SourceInterpreter.GetAllStateEntries(r.Item2, this.m_parent.m_updateTranslator,
this.m_parent.m_table));
}
};
addStateEntries(leftInsert);
addStateEntries(leftDelete);
addStateEntries(rightInsert);
addStateEntries(rightDelete);
throw EntityUtil.Update(Strings.Update_InvalidChanges, null, stateEntries);
}
// Where needed, substitute null/unknown placeholders. In some of the join propagation
// rules, we handle the case where a side of the join is 'unknown', or where one side
// of a join is comprised of an record containing only nulls. For instance, we may update
// only one extent appearing in a row of a table (unknown), or; we may insert only
// the left hand side of a left outer join, in which case the right hand side is 'null'.
if (0 != (Ops.LeftUnknown & insertRule))
{
leftInsert = Tuple.Create(key, LeftPlaceholder(key, PopulateMode.Unknown));
}
if (0 != (Ops.LeftUnknown & deleteRule))
{
leftDelete = Tuple.Create(key, LeftPlaceholder(key, PopulateMode.Unknown));
}
if (0 != (Ops.RightNullModified & insertRule))
{
rightInsert = Tuple.Create(key, RightPlaceholder(key, PopulateMode.NullModified));
}
else if (0 != (Ops.RightNullPreserve & insertRule))
{
rightInsert = Tuple.Create(key, RightPlaceholder(key, PopulateMode.NullPreserve));
}
else if (0 != (Ops.RightUnknown & insertRule))
{
rightInsert = Tuple.Create(key, RightPlaceholder(key, PopulateMode.Unknown));
}
if (0 != (Ops.RightNullModified & deleteRule))
{
rightDelete = Tuple.Create(key, RightPlaceholder(key, PopulateMode.NullModified));
}
else if (0 != (Ops.RightNullPreserve & deleteRule))
{
rightDelete = Tuple.Create(key, RightPlaceholder(key, PopulateMode.NullPreserve));
}
else if (0 != (Ops.RightUnknown & deleteRule))
{
rightDelete = Tuple.Create(key, RightPlaceholder(key, PopulateMode.Unknown));
}
// Populate elements in join output
if (null != leftInsert && null != rightInsert)
{
result.Inserted.Add(CreateResultTuple(leftInsert, rightInsert, result));
}
if (null != leftDelete && null != rightDelete)
{
result.Deleted.Add(CreateResultTuple(leftDelete, rightDelete, result));
}
}
// Processes all insert and delete requests in the table's <see cref="ChangeNode" />. Inserts
// and deletes with the same key are merged into updates.
internal List <UpdateCommand> CompileCommands(ChangeNode changeNode, UpdateCompiler compiler)
{
Set <CompositeKey> keys = new Set <CompositeKey>(compiler.m_translator.KeyComparer);
// Retrieve all delete results (original values) and insert results (current values) while
// populating a set of all row keys. The set contains a single key per row.
Dictionary <CompositeKey, PropagatorResult> deleteResults = ProcessKeys(compiler, changeNode.Deleted, keys);
Dictionary <CompositeKey, PropagatorResult> insertResults = ProcessKeys(compiler, changeNode.Inserted, keys);
List <UpdateCommand> commands = new List <UpdateCommand>(deleteResults.Count + insertResults.Count);
// Examine each row key to see if the row is being deleted, inserted or updated
foreach (CompositeKey key in keys)
{
PropagatorResult deleteResult;
PropagatorResult insertResult;
bool hasDelete = deleteResults.TryGetValue(key, out deleteResult);
bool hasInsert = insertResults.TryGetValue(key, out insertResult);
Debug.Assert(hasDelete || hasInsert, "(update/TableChangeProcessor) m_keys must not contain a value " +
"if there is no corresponding insert or delete");
try
{
if (!hasDelete)
{
// this is an insert
commands.Add(compiler.BuildInsertCommand(insertResult, this));
}
else if (!hasInsert)
{
// this is a delete
commands.Add(compiler.BuildDeleteCommand(deleteResult, this));
}
else
{
// this is an update because it has both a delete result and an insert result
UpdateCommand updateCommand = compiler.BuildUpdateCommand(deleteResult, insertResult, this);
if (null != updateCommand)
{
// if null is returned, it means it is a no-op update
commands.Add(updateCommand);
}
}
}
catch (Exception e)
{
if (UpdateTranslator.RequiresContext(e))
{
// collect state entries in scope for the current compilation
List <IEntityStateEntry> stateEntries = new List <IEntityStateEntry>();
if (null != deleteResult)
{
stateEntries.AddRange(SourceInterpreter.GetAllStateEntries(
deleteResult, compiler.m_translator, m_table));
}
if (null != insertResult)
{
stateEntries.AddRange(SourceInterpreter.GetAllStateEntries(
insertResult, compiler.m_translator, m_table));
}
throw EntityUtil.Update(System.Data.Entity.Strings.Update_GeneralExecutionException,
e, stateEntries);
}
throw;
}
}
return(commands);
}
