public override void Visit(DbScanExpression expression)
{
Check.NotNull(expression, "expression");
// we know we won't hit this code unless there is no function defined for this
// ModificationOperation, so if this EntitySet is using a DefiningQuery, instead
// of a table, that is an error
MetadataProperty definingQuery;
if (expression.Target.MetadataProperties.TryGetValue("DefiningQuery", false, out definingQuery)
&&
null != definingQuery.Value)
{
string missingCudElement;
var ict = _commandTree as DbInsertCommandTree;
var dct = _commandTree as DbDeleteCommandTree;
#if DEBUG
var uct = _commandTree as DbUpdateCommandTree;
#endif
if (null != dct)
{
missingCudElement = "DeleteFunction" /*StorageMslConstructs.DeleteFunctionElement*/;
}
else if (null != ict)
{
missingCudElement = "InsertFunction" /*StorageMslConstructs.InsertFunctionElement*/;
}
else
{
#if DEBUG
Debug.Assert(null != uct, "did you add a new option?");
#endif
missingCudElement = "UpdateFunction" /*StorageMslConstructs.UpdateFunctionElement*/;
}
throw ADP1.Update(
EntityRes.GetString(
EntityRes.Update_SqlEntitySetWithoutDmlFunctions,
expression.Target.Name,
missingCudElement,
"ModificationFunctionMapping" /*StorageMslConstructs.ModificationFunctionMappingElement*/),
null);
}
_commandText.Append(SqlGenerator.GetTargetTSql(expression.Target));
}
internal static string[] GenerateUpdateSql(DbUpdateCommandTree tree, out List <DbParameter> parameters, bool isLocalProvider)
{
var commandTexts = new List <String>();
var commandText = new StringBuilder(s_commandTextBuilderInitialCapacity);
var translator = new ExpressionTranslator(commandText, tree, null != tree.Returning, isLocalProvider);
// update [schemaName].[tableName]
commandText.Append("update ");
tree.Target.Expression.Accept(translator);
commandText.AppendLine();
// set c1 = ..., c2 = ..., ...
var first = true;
commandText.Append("set ");
foreach (DbSetClause setClause in tree.SetClauses)
{
if (first)
{
first = false;
}
else
{
commandText.Append(", ");
}
setClause.Property.Accept(translator);
commandText.Append(" = ");
setClause.Value.Accept(translator);
}
if (first)
{
// If first is still true, it indicates there were no set
// clauses.
// - we acquire the appropriate locks
// - server-gen columns (e.g. timestamp) get recomputed
//
// Fix #13533 : A fake update DML updating some column item
// with the same value as before to acquire the lock on the table
// while updating some columns in another table. This happens when
// both the table are dependent on an entity and the members of entity
// which is mapped to one table is being updated and the other table
// needs to be locked for consistency.
string updatableColumnName;
if (GetUpdatableColumn(tree, out updatableColumnName))
{
commandText.Append("[");
commandText.Append(CommonUtils.EscapeSquareBraceNames(updatableColumnName));
commandText.Append("] ");
commandText.Append(" = ");
commandText.Append("[");
commandText.Append(CommonUtils.EscapeSquareBraceNames(updatableColumnName));
commandText.Append("] ");
}
else
{
// Throw some meaningful error
throw ADP1.Update(
EntityRes.GetString(EntityRes.UpdateStatementCannotBeGeneratedForAcquiringLock),
null);
}
}
commandText.AppendLine();
// where c1 = ..., c2 = ...
commandText.Append("where ");
tree.Predicate.Accept(translator);
commandText.AppendLine();
commandTexts.Add(commandText.ToString());
commandText.Length = 0;
// generate returning sql
GenerateReturningSql(commandText, tree, translator, tree.Returning);
if (!String.IsNullOrEmpty(commandText.ToString()))
{
commandTexts.Add(commandText.ToString());
}
parameters = translator.Parameters;
return(commandTexts.ToArray());
}
