private Expression GetIdentityCheck(DbTableExpression root, MappingEntity entity, Expression instance, MappingTable table)
{
if (this.mapping.IsExtensionTable(table))
{
var keyColNames = this.mapping.GetExtensionKeyColumnNames(table).ToArray();
var relatedMembers = this.mapping.GetExtensionRelatedMembers(table).ToArray();
var where = null as Expression;
for (int i = 0, n = keyColNames.Length; i < n; i++)
{
var relatedMember = relatedMembers[i];
var cex = new DbColumnExpression(TypeHelper.GetMemberType(relatedMember), this.GetColumnType(entity, relatedMember), root.Alias, keyColNames[n]);
var nex = this.GetMemberExpression(instance, entity, relatedMember);
var eq = cex.Equal(nex);
where = (where != null) ? where.And(eq) : where;
}
return(where);
}
return(base.GetIdentityCheck(root, entity, instance));
}
internal override DbProjectionExpression GetQueryExpression(MappingEntity entity)
{
var tables = this.mapping.GetTables(entity);
if (tables.Count <= 1)
{
return(base.GetQueryExpression(entity));
}
var aliases = new Dictionary <string, TableAlias>();
var rootTable = tables.Single(ta => !this.mapping.IsExtensionTable(ta));
var tex = new DbTableExpression(new TableAlias(), entity, this.mapping.GetTableName(rootTable));
aliases.Add(this.mapping.GetAlias(rootTable), tex.Alias);
var source = tex as Expression;
foreach (var table in tables.Where(t => this.mapping.IsExtensionTable(t)))
{
var joinedTableAlias = new TableAlias();
var extensionAlias = this.mapping.GetAlias(table);
aliases.Add(extensionAlias, joinedTableAlias);
var keyColumns = this.mapping.GetExtensionKeyColumnNames(table).ToList();
var relatedMembers = this.mapping.GetExtensionRelatedMembers(table).ToList();
var relatedAlias = this.mapping.GetExtensionRelatedAlias(table);
aliases.TryGetValue(relatedAlias, out TableAlias relatedTableAlias);
var joinedTex = new DbTableExpression(joinedTableAlias, entity, this.mapping.GetTableName(table));
var cond = null as Expression;
for (int i = 0, n = keyColumns.Count; i < n; i++)
{
var memberType = TypeHelper.GetMemberType(relatedMembers[i]);
var colType = this.GetColumnType(entity, relatedMembers[i]);
var relatedColumn = new DbColumnExpression(memberType, colType, relatedTableAlias, this.mapping.GetColumnName(entity, relatedMembers[i]));
var joinedColumn = new DbColumnExpression(memberType, colType, joinedTableAlias, keyColumns[i]);
var eq = joinedColumn.Equal(relatedColumn);
cond = (cond != null) ? cond.And(eq) : eq;
}
source = new DbJoinExpression(JoinType.SingletonLeftOuter, source, joinedTex, cond);
}
var columns = new List <DbColumnDeclaration>();
this.GetColumns(entity, aliases, columns);
var root = new DbSelectExpression(new TableAlias(), columns, source, null);
var existingAliases = aliases.Values.ToArray();
var projector = this.GetEntityExpression(root, entity) as Expression;
var selectAlias = new TableAlias();
var pc = DbColumnProjector.ProjectColumns(this.Translator.Linguist.Language, projector, null, selectAlias, root.Alias);
var proj = new DbProjectionExpression
(
new DbSelectExpression(selectAlias, pc.Columns, root, null),
pc.Projector
);
return(this.Translator.Police.ApplyPolicy(proj, entity.ElementType.GetTypeInfo()) as DbProjectionExpression);
}