private static bool UpdateColumnNamesForTableSharing( DbDatabaseMapping databaseMapping, EntityType entityType, EntityType toTable, StorageMappingFragment fragment) { // Validate: this table can be used only if: // 1. The table is not used by any other type // 2. The table is used only by types in the same type hierarchy (TPH) // 3. There is a 1:1 relationship and the PK count and types match (Table Splitting) var typesSharingTable = FindAllTypesUsingTable(databaseMapping, toTable); var associationsToSharedTable = new Dictionary<EntityType, List<AssociationType>>(); foreach (var candidateType in typesSharingTable) { var oneToOneAssocations = FindAllOneToOneFKAssociationTypes( databaseMapping.Model, entityType, candidateType); var rootType = candidateType.GetRootType(); if (!associationsToSharedTable.ContainsKey(rootType)) { associationsToSharedTable.Add(rootType, oneToOneAssocations.ToList()); } else { associationsToSharedTable[rootType].AddRange(oneToOneAssocations); } } foreach (var candidateTypePair in associationsToSharedTable) { // Check if these types are in a TPH hierarchy if (candidateTypePair.Key != entityType.GetRootType() && candidateTypePair.Value.Count == 0) { var tableName = toTable.GetTableName(); throw Error.EntityMappingConfiguration_InvalidTableSharing( entityType.Name, candidateTypePair.Key.Name, tableName != null ? tableName.Name : databaseMapping.Database.GetEntitySet(toTable).Table); } } var allAssociations = associationsToSharedTable.Values.SelectMany(l => l); if (allAssociations.Any()) { var principalKeyNamesType = toTable.GetKeyNamesType(); if (principalKeyNamesType == null) { // grab a candidate var association = allAssociations.First(); principalKeyNamesType = association.Constraint.FromRole.GetEntityType(); if (allAssociations.All(x => x.Constraint.FromRole.GetEntityType() == principalKeyNamesType)) { toTable.SetKeyNamesType(principalKeyNamesType); } } // rename the columns in the fragment to match the principal keys var principalKeys = principalKeyNamesType.KeyProperties().ToArray(); var i = 0; foreach (var k in entityType.KeyProperties()) { var dependentColumn = fragment.ColumnMappings.Single(pm => pm.PropertyPath.First() == k).ColumnProperty; dependentColumn.Name = principalKeys[i].Name; i++; } return true; } return false; }