private void ExecuteBatchMultipleCommands(UpdateSet updateSet)
{
//Note: for multiple commands, we cannot include trans statements into batch commands, like add 'Begin Trans' to the first command
// and 'Commit' to the last command - this will fail. We start/commit trans using separate calls
// Also, we have to manage connection explicitly, to start/commit transaction
var conn = updateSet.Connection;
try {
var inNewTrans = conn.DbTransaction == null;
if (inNewTrans)
{
conn.BeginTransaction(commitOnSave: true);
}
foreach (var batchCmd in updateSet.BatchCommands)
{
ExecuteDbCommand(batchCmd.DbCommand, conn, DbExecutionType.NonQuery);
if (batchCmd.HasActions)
{
foreach (var action in batchCmd.GetPostActions())
{
action();
}
}
}//foreach
if (inNewTrans)
{
conn.Commit();
}
ReleaseConnection(conn);
} catch {
ReleaseConnection(conn, inError: true);
throw;
}
}
// Note: scheduled commands are already in batch commands
private void SaveChangesInBatchMode(UpdateSet updateSet)
{
var session = updateSet.Session;
var postExecActions = new List <Action>();
var batchBuilder = new DbBatchCommandSetBuilder(this, updateSet);
batchBuilder.Build();
LogComment(session, "-- BEGIN BATCH ({0} rows, {1} batch command(s)) ---------------------------", updateSet.AllRecords.Count, updateSet.BatchCommands.Count);
if (updateSet.BatchCommands.Count == 1)
{
ExecuteBatchSingleCommand(updateSet);
}
else
{
ExecuteBatchMultipleCommands(updateSet);
}
LogComment(session, "-- END BATCH --------------------------------------\r\n");
//execute post-execute actions; it is usually handling output parameter values
// Finalize records after update
foreach (var rec in updateSet.AllRecords)
{
rec.CustomTag = null; //clear temp ref that batch process has set
rec.SubmitCount++;
rec.EntityInfo.SaveEvents.OnSubmittedChanges(rec);
}
}
private void ExecuteBatchSingleCommand(UpdateSet updateSet)
{
var conn = updateSet.Connection;
try {
var batchCmd = updateSet.BatchCommands[0];
var dbCmd = batchCmd.DbCommand;
if (conn.DbTransaction == null) //surround it with beginTrans/commit
{
dbCmd.CommandText = string.Format("{0}\r\n{1}\r\n{2}", _driver.BatchBeginTransaction, dbCmd.CommandText, _driver.BatchCommitTransaction);
}
ExecuteDbCommand(dbCmd, conn, DbExecutionType.NonQuery);
if (batchCmd.HasActions)
{
foreach (var action in batchCmd.GetPostActions())
{
action();
}
}
ReleaseConnection(conn);
} catch {
ReleaseConnection(conn, inError: true);
throw;
}
}
public void SaveChanges(EntitySession session)
{
if (session.HasChanges())
{
var records = session.RecordsChanged.Where(rec => ShouldUpdate(rec)).ToList();
var conn = GetConnection(session);
var updateSet = new UpdateSet(conn, _timeService.UtcNow, records);
var batchMode = ShouldUseBatchMode(updateSet);
if (batchMode)
{
SaveChangesInBatchMode(updateSet);
}
else
{
SaveChangesNoBatch(session, updateSet);
}
}
//commit if we have session connection with transaction and CommitOnSave
var sConn = session.CurrentConnection;
if (sConn != null)
{
if (sConn.DbTransaction != null && sConn.Flags.IsSet(ConnectionFlags.CommitOnSave))
{
sConn.Commit();
}
if (sConn.Lifetime != ConnectionLifetime.Explicit)
{
ReleaseConnection(sConn);
}
}
session.ScheduledCommands.Clear();
}
public DbBatchCommandSetBuilder(Database db, UpdateSet updateSet)
{
_db = db;
_driver = _db.DbModel.Driver;
_updateSet = updateSet;
// Clear identity holders in record.CustomTag
if (_updateSet.UsesOutParams)
foreach (var rec in updateSet.AllRecords)
rec.CustomTag = null;
}
public DbBatchCommandSetBuilder(Database db, UpdateSet updateSet)
{
_db = db;
_driver = _db.DbModel.Driver;
_updateSet = updateSet;
// Clear identity holders in record.CustomTag
if (_updateSet.UsesOutParams)
{
foreach (var rec in updateSet.AllRecords)
{
rec.CustomTag = null;
}
}
}
private void ExecuteBatchSingleCommand(UpdateSet updateSet)
{
var conn = updateSet.Connection;
try {
var batchCmd = updateSet.BatchCommands[0];
var dbCmd = batchCmd.DbCommand;
if (conn.DbTransaction == null) //surround it with beginTrans/commit
dbCmd.CommandText = string.Format("{0}\r\n{1}\r\n{2}", _driver.BatchBeginTransaction, dbCmd.CommandText, _driver.BatchCommitTransaction);
ExecuteDbCommand(dbCmd, conn, DbExecutionType.NonQuery);
if (batchCmd.HasActions)
foreach (var action in batchCmd.GetPostActions())
action();
ReleaseConnection(conn);
} catch {
ReleaseConnection(conn, inError: true);
throw;
}
}
// Checks if batch is needed (record count > 1); and driver supports batch mode, and if batch is not disabled;
// If there are any out params for CRUD stored procs (identity, timestamp) then driver should out param for batch mode
// MS SQL supports batch with output params; SQL CE does not support batch at all - one statement at a time.
// MySql and Postgres support batch, but there are some troubles in using output parameters inside the batch,
// so for these drivers batch OutParamsInBatchMode is not set, so we do not use batch mode if there are any.
private bool ShouldUseBatchMode(UpdateSet updateSet)
{
var totalCount = updateSet.AllRecords.Count + updateSet.Session.ScheduledCommands.Count;
if (totalCount > 1 && Settings.ModelConfig.Options.IsSet(DbOptions.UseBatchMode))
{
//Probably we should use batch mode; check if it is disabled or stored procs are disabled
if (updateSet.Session.Options.IsSet(EntitySessionOptions.DisableBatch | EntitySessionOptions.DisableStoredProcs))
{
return(false);
}
// check if there any out params
if (updateSet.UsesOutParams && !_driver.Supports(DbFeatures.OutParamsInBatchedUpdates))
{
return(false);
}
//otherwise return true
return(true);
}
return(false);
}
// Note: scheduled commands are already in batch commands
private void SaveChangesInBatchMode(UpdateSet updateSet)
{
var session = updateSet.Session;
var postExecActions = new List<Action>();
var batchBuilder = new DbBatchCommandSetBuilder(this, updateSet);
batchBuilder.Build();
LogComment(session, "-- BEGIN BATCH ({0} rows, {1} batch command(s)) ---------------------------", updateSet.AllRecords.Count, updateSet.BatchCommands.Count);
if (updateSet.BatchCommands.Count == 1) {
ExecuteBatchSingleCommand(updateSet);
} else {
ExecuteBatchMultipleCommands(updateSet);
}
LogComment(session, "-- END BATCH --------------------------------------\r\n");
//execute post-execute actions; it is usually handling output parameter values
// Finalize records after update
foreach (var rec in updateSet.AllRecords) {
rec.CustomTag = null; //clear temp ref that batch process has set
rec.SubmitCount++;
rec.EntityInfo.SaveEvents.OnSubmittedChanges(rec);
}
}
private void ExecuteBatchMultipleCommands(UpdateSet updateSet)
{
//Note: for multiple commands, we cannot include trans statements into batch commands, like add 'Begin Trans' to the first command
// and 'Commit' to the last command - this will fail. We start/commit trans using separate calls
// Also, we have to manage connection explicitly, to start/commit transaction
var conn = updateSet.Connection;
try {
var inNewTrans = conn.DbTransaction == null;
if (inNewTrans)
conn.BeginTransaction(commitOnSave: true);
foreach (var batchCmd in updateSet.BatchCommands) {
ExecuteDbCommand(batchCmd.DbCommand, conn, DbExecutionType.NonQuery);
if (batchCmd.HasActions)
foreach (var action in batchCmd.GetPostActions())
action();
}//foreach
if (inNewTrans)
conn.Commit();
ReleaseConnection(conn);
} catch {
ReleaseConnection(conn, inError: true);
throw;
}
}
private void SaveChangesNoBatch(EntitySession session, UpdateSet updateSet)
{
var conn = updateSet.Connection;
var withTrans = conn.DbTransaction == null && updateSet.UseTransaction;
try {
var start = CurrentTickCount;
if (withTrans)
{
conn.BeginTransaction(commitOnSave: true);
}
//execute commands
if (session.ScheduledCommands.Count > 0)
{
ExecuteScheduledCommands(conn, session, CommandSchedule.TransactionStart);
}
//Apply record updates
foreach (var rec in updateSet.AllRecords)
{
ApplyUpdate(conn, rec);
}
//Execute scheduled commands
if (session.ScheduledCommands.Count > 0)
{
ExecuteScheduledCommands(conn, session, CommandSchedule.TransactionEnd);
}
if (conn.DbTransaction != null && conn.Flags.IsSet(ConnectionFlags.CommitOnSave))
{
conn.Commit();
}
ReleaseConnection(conn);
} catch {
ReleaseConnection(conn, inError: true);
throw;
}
}
private void SaveChangesNoBatch(EntitySession session, UpdateSet updateSet)
{
var conn = updateSet.Connection;
var withTrans = conn.DbTransaction == null && updateSet.UseTransaction;
try {
var start = CurrentTickCount;
if(withTrans)
conn.BeginTransaction(commitOnSave: true);
//execute commands
if (session.ScheduledCommands.Count > 0)
ExecuteScheduledCommands(conn, session, CommandSchedule.TransactionStart);
//Apply record updates
foreach(var rec in updateSet.AllRecords)
ApplyUpdate(conn, rec);
//Execute scheduled commands
if (session.ScheduledCommands.Count > 0)
ExecuteScheduledCommands(conn, session, CommandSchedule.TransactionEnd);
if (conn.DbTransaction != null && conn.Flags.IsSet(ConnectionFlags.CommitOnSave))
conn.Commit();
ReleaseConnection(conn);
} catch {
ReleaseConnection(conn, inError: true);
throw;
}
}
public void SaveChanges(EntitySession session)
{
if (session.HasChanges()) {
var records = session.RecordsChanged.Where(rec => ShouldUpdate(rec)).ToList();
var conn = GetConnection(session);
var updateSet = new UpdateSet(conn, _timeService.UtcNow, records);
var batchMode = ShouldUseBatchMode(updateSet);
if (batchMode)
SaveChangesInBatchMode(updateSet);
else
SaveChangesNoBatch(session, updateSet);
}
//commit if we have session connection with transaction and CommitOnSave
var sConn = session.CurrentConnection;
if (sConn != null) {
if (sConn.DbTransaction != null && sConn.Flags.IsSet(ConnectionFlags.CommitOnSave))
sConn.Commit();
if (sConn.Lifetime != ConnectionLifetime.Explicit)
ReleaseConnection(sConn);
}
session.ScheduledCommands.Clear();
}
// Checks if batch is needed (record count > 1); and driver supports batch mode, and if batch is not disabled;
// If there are any out params for CRUD stored procs (identity, timestamp) then driver should out param for batch mode
// MS SQL supports batch with output params; SQL CE does not support batch at all - one statement at a time.
// MySql and Postgres support batch, but there are some troubles in using output parameters inside the batch,
// so for these drivers batch OutParamsInBatchMode is not set, so we do not use batch mode if there are any.
private bool ShouldUseBatchMode(UpdateSet updateSet)
{
var totalCount = updateSet.AllRecords.Count + updateSet.Session.ScheduledCommands.Count;
if (totalCount > 1 && Settings.ModelConfig.Options.IsSet(DbOptions.UseBatchMode)) {
//Probably we should use batch mode; check if it is disabled or stored procs are disabled
if(updateSet.Session.Options.IsSet(EntitySessionOptions.DisableBatch | EntitySessionOptions.DisableStoredProcs))
return false;
// check if there any out params
if(updateSet.UsesOutParams && !_driver.Supports(DbFeatures.OutParamsInBatchedUpdates))
return false;
//otherwise return true
return true;
}
return false;
}
