public static int DeleteFromQuery <T>(this IQueryable <T> querable, BulkDeleteOptions <T> options)
{
int rowAffected = 0;
var dbQuery = querable as DbQuery <T>;
var dbConnection = GetSqlConnectionFromIQuerable(querable);
//Open datbase connection
if (dbConnection.State == ConnectionState.Closed)
{
dbConnection.Open();
}
using (var dbTransaction = dbConnection.BeginTransaction())
{
try
{
var sqlQuery = SqlQuery.Parse(dbQuery.Sql);
sqlQuery.ChangeToDelete("[Extent1]");
rowAffected = SqlUtil.ExecuteSql(sqlQuery.Sql, dbConnection, dbTransaction, options);
dbTransaction.Commit();
}
catch (Exception ex)
{
dbTransaction.Rollback();
throw ex;
}
finally
{
dbConnection.Close();
}
}
return(rowAffected);
}
public static int BulkDelete <T>(this DbContext context, IEnumerable <T> entities, BulkDeleteOptions <T> options)
{
int rowsAffected = 0;
var tableMapping = context.GetTableMapping(typeof(T));
Validate(tableMapping);
var dbConnection = context.GetSqlConnection();
if (dbConnection.State == ConnectionState.Closed)
{
dbConnection.Open();
}
using (var transaction = dbConnection.BeginTransaction())
{
try
{
string stagingTableName = GetStagingTableName(tableMapping, options.UsePermanentTable, dbConnection);
string destinationTableName = string.Format("[{0}].[{1}]", tableMapping.Schema, tableMapping.TableName);
string[] storeGeneratedColumnNames = tableMapping.Columns.Where(o => o.Column.IsStoreGeneratedIdentity).Select(o => o.Column.Name).ToArray();
string deleteCondition = string.Join(" AND ", storeGeneratedColumnNames.Select(o => string.Format("s.{0}=t.{0}", o)));
SqlUtil.CloneTable(destinationTableName, stagingTableName, storeGeneratedColumnNames, dbConnection, transaction);
BulkInsert(entities, options, tableMapping, dbConnection, transaction, stagingTableName, storeGeneratedColumnNames, SqlBulkCopyOptions.KeepIdentity);
string deleteSql = string.Format("DELETE t FROM {0} s JOIN {1} t ON {2}", stagingTableName, destinationTableName, deleteCondition);
rowsAffected = SqlUtil.ExecuteSql(deleteSql, dbConnection, transaction);
SqlUtil.DeleteTable(stagingTableName, dbConnection, transaction);
transaction.Commit();
}
catch (Exception ex)
{
transaction.Rollback();
throw ex;
}
finally
{
dbConnection.Close();
}
return(rowsAffected);
}
}
