You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

353 lines
12 KiB

#if MYSQL_6_10
// Copyright ?2006, 2019, Oracle and/or its affiliates. All rights reserved.
//
// MySQL Connector/NET is licensed under the terms of the GPLv2
// <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most
// MySQL Connectors. There are special exceptions to the terms and
// conditions of the GPLv2 as it is applied to this software, see the
// FLOSS License Exception
// <http://www.mysql.com/about/legal/licensing/foss-exception.html>.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published
// by the Free Software Foundation; version 2 of the License.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
using System;
using System.Collections.Generic;
using System.Data;
using System.Text;
using System.Threading.Tasks;
using System.Threading;
using System.IO;
namespace Externals.MySql.Data.MySqlClient
{
/// <summary>
/// Allows importing large amounts of data into a database with bulk loading.
/// </summary>
internal class MySqlBulkLoader
{
// constant values
private const string defaultFieldTerminator = "\t";
private const string defaultLineTerminator = "\n";
private const char defaultEscapeCharacter = '\\';
// fields
public MySqlBulkLoader(MySqlConnection connection)
{
Connection = connection;
Local = false;
FieldTerminator = defaultFieldTerminator;
LineTerminator = defaultLineTerminator;
FieldQuotationCharacter = Char.MinValue;
ConflictOption = MySqlBulkLoaderConflictOption.None;
Columns = new List<string>();
Expressions = new List<string>();
}
#region Properties
/// <summary>
/// Gets or sets the connection.
/// </summary>
/// <value>The connection.</value>
public MySqlConnection Connection { get; set; }
/// <summary>
/// Gets or sets the field terminator.
/// </summary>
/// <value>The field terminator.</value>
public string FieldTerminator { get; set; }
/// <summary>
/// Gets or sets the line terminator.
/// </summary>
/// <value>The line terminator.</value>
public string LineTerminator { get; set; }
/// <summary>
/// Gets or sets the name of the table.
/// </summary>
/// <value>The name of the table.</value>
public string TableName { get; set; }
/// <summary>
/// Gets or sets the character set.
/// </summary>
/// <value>The character set.</value>
public string CharacterSet { get; set; }
/// <summary>
/// Gets or sets the name of the file.
/// </summary>
/// <value>The name of the file.</value>
public string FileName { get; set; }
/// <summary>
/// Gets or sets the timeout.
/// </summary>
/// <value>The timeout.</value>
public int Timeout { get; set; }
/// <summary>
/// Gets or sets a value indicating whether the file name that is to be loaded
/// is local to the client or not. The default value is false.
/// </summary>
/// <value><c>true</c> if local; otherwise, <c>false</c>.</value>
public bool Local { get; set; }
/// <summary>
/// Gets or sets the number of lines to skip.
/// </summary>
/// <value>The number of lines to skip.</value>
public int NumberOfLinesToSkip { get; set; }
/// <summary>
/// Gets or sets the line prefix.
/// </summary>
/// <value>The line prefix.</value>
public string LinePrefix { get; set; }
/// <summary>
/// Gets or sets the field quotation character.
/// </summary>
/// <value>The field quotation character.</value>
public char FieldQuotationCharacter { get; set; }
/// <summary>
/// Gets or sets a value indicating whether [field quotation optional].
/// </summary>
/// <value>
/// <c>true</c> if [field quotation optional]; otherwise, <c>false</c>.
/// </value>
public bool FieldQuotationOptional { get; set; }
/// <summary>
/// Gets or sets the escape character.
/// </summary>
/// <value>The escape character.</value>
public char EscapeCharacter { get; set; }
/// <summary>
/// Gets or sets the conflict option.
/// </summary>
/// <value>The conflict option.</value>
public MySqlBulkLoaderConflictOption ConflictOption { get; set; }
/// <summary>
/// Gets or sets the priority.
/// </summary>
/// <value>The priority.</value>
public MySqlBulkLoaderPriority Priority { get; set; }
/// <summary>
/// Gets the columns.
/// </summary>
/// <value>The columns.</value>
public List<string> Columns { get; }
/// <summary>
/// Gets the expressions.
/// </summary>
/// <value>The expressions.</value>
public List<string> Expressions { get; }
#endregion
/// <summary>
/// Executes the load operation.
/// </summary>
/// <returns>The number of rows inserted.</returns>
public int Load()
{
bool openedConnection = false;
if (Connection == null)
throw new InvalidOperationException(Resources.ConnectionNotSet);
// next we open up the connetion if it is not already open
if (Connection.State != ConnectionState.Open)
{
openedConnection = true;
Connection.Open();
}
try
{
string sql = BuildSqlCommand();
MySqlCommand cmd = new MySqlCommand(sql, Connection) { CommandTimeout = Timeout };
return cmd.ExecuteNonQuery();
}
finally
{
if (openedConnection)
Connection.Close();
}
}
#region Async
/// <summary>
/// Asynchronous version of the load operation.
/// </summary>
/// <returns>The number of rows inserted.</returns>
public Task<int> LoadAsync()
{
return LoadAsync(CancellationToken.None);
}
/// <summary>
/// Executes the load operation asynchronously while the cancellation isn't requested.
/// </summary>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>The number of rows inserted.</returns>
public Task<int> LoadAsync(CancellationToken cancellationToken)
{
var result = new TaskCompletionSource<int>();
if (cancellationToken == CancellationToken.None || !cancellationToken.IsCancellationRequested)
{
try
{
int loadResult = Load();
result.SetResult(loadResult);
}
catch (Exception ex)
{
result.SetException(ex);
}
}
else
{
result.SetCanceled();
}
return result.Task;
}
#endregion
private string BuildSqlCommand()
{
StringBuilder sql = new StringBuilder("LOAD DATA ");
if (Priority == MySqlBulkLoaderPriority.Low)
sql.Append("LOW_PRIORITY ");
else if (Priority == MySqlBulkLoaderPriority.Concurrent)
sql.Append("CONCURRENT ");
if (Local)
sql.Append("LOCAL ");
sql.Append("INFILE ");
if (Path.DirectorySeparatorChar == '\\')
sql.AppendFormat("'{0}' ", FileName.Replace(@"\", @"\\"));
else
sql.AppendFormat("'{0}' ", FileName);
if (ConflictOption == MySqlBulkLoaderConflictOption.Ignore)
sql.Append("IGNORE ");
else if (ConflictOption == MySqlBulkLoaderConflictOption.Replace)
sql.Append("REPLACE ");
sql.AppendFormat("INTO TABLE {0} ", TableName);
if (CharacterSet != null)
sql.AppendFormat("CHARACTER SET {0} ", CharacterSet);
StringBuilder optionSql = new StringBuilder(String.Empty);
if (FieldTerminator != defaultFieldTerminator)
optionSql.AppendFormat("TERMINATED BY '{0}' ", FieldTerminator);
if (FieldQuotationCharacter != Char.MinValue)
optionSql.AppendFormat("{0} ENCLOSED BY '{1}' ",
FieldQuotationOptional ? "OPTIONALLY" : "", FieldQuotationCharacter);
if (EscapeCharacter != defaultEscapeCharacter &&
EscapeCharacter != Char.MinValue)
optionSql.AppendFormat("ESCAPED BY '{0}' ", EscapeCharacter);
if (optionSql.Length > 0)
sql.AppendFormat("FIELDS {0}", optionSql.ToString());
optionSql = new StringBuilder(String.Empty);
if (!string.IsNullOrEmpty(LinePrefix))
optionSql.AppendFormat("STARTING BY '{0}' ", LinePrefix);
if (LineTerminator != defaultLineTerminator)
optionSql.AppendFormat("TERMINATED BY '{0}' ", LineTerminator);
if (optionSql.Length > 0)
sql.AppendFormat("LINES {0}", optionSql.ToString());
if (NumberOfLinesToSkip > 0)
sql.AppendFormat("IGNORE {0} LINES ", NumberOfLinesToSkip);
if (Columns.Count > 0)
{
sql.Append("(");
sql.Append(Columns[0]);
for (int i = 1; i < Columns.Count; i++)
sql.AppendFormat(",{0}", Columns[i]);
sql.Append(") ");
}
if (Expressions.Count > 0)
{
sql.Append("SET ");
sql.Append(Expressions[0]);
for (int i = 1; i < Expressions.Count; i++)
sql.AppendFormat(",{0}", Expressions[i]);
}
return sql.ToString();
}
}
/// <summary>
/// Represents the priority set for bulk loading operations.
/// </summary>
internal enum MySqlBulkLoaderPriority
{
/// <summary>
/// This is the default and indicates normal priority
/// </summary>
None,
/// <summary>
/// Low priority will cause the load operation to wait until all readers of the table
/// have finished. This only affects storage engines that use only table-level locking
/// such as MyISAM, Memory, and Merge.
/// </summary>
Low,
/// <summary>
/// Concurrent priority is only relevant for MyISAM tables and signals that if the table
/// has no free blocks in the middle that other readers can retrieve data from the table
/// while the load operation is happening.
/// </summary>
Concurrent
}
/// <summary>
/// Represents the behavior when conflicts arise during bulk loading operations.
/// </summary>
internal enum MySqlBulkLoaderConflictOption
{
/// <summary>
/// This is the default and indicates normal operation. In the event of a LOCAL load, this
/// is the same as ignore. When the data file is on the server, then a key conflict will
/// cause an error to be thrown and the rest of the data file ignored.
/// </summary>
None,
/// <summary>
/// Replace column values when a key conflict occurs.
/// </summary>
Replace,
/// <summary>
/// Ignore any rows where the primary key conflicts.
/// </summary>
Ignore
}
}
#endif