/// <summary>
/// 将制定的数据复制到当前数据访问对象关联的数据库中
/// </summary>
/// <param name="log">事务日志实体</param>
/// <returns>如果数据已经存在或者复制成功，返回真；如果遇到错误，返回假</returns>
public bool DataReplication(MyCommandLogEntity log)
{
this.ErrorMessage = string.Empty;
this.CurrentStatus = ReplicationStatus.UnKnown;
if (log.LogFlag > 0)
{
this.CurrentStatus = ReplicationStatus.Executed;
return(true);
}
var query = this.NewQuery <MyCommandLogEntity>();
if (query.ExistsEntity(log))
{
this.CurrentStatus = ReplicationStatus.LogExists;
return(true);
}
else
{
string errorMessage;
MyCommandLogEntity newLog = new MyCommandLogEntity();
newLog.CommandID = log.CommandID;
newLog.CommandName = log.CommandName;
newLog.CommandText = log.CommandText;
newLog.CommandType = log.CommandType;
newLog.ExecuteTime = DateTime.Now; //新执行的时间
newLog.LogFlag = 2; //表示已经复制到目标库的状态
newLog.ParameterInfo = log.ParameterInfo;
newLog.SQLType = log.SQLType;
newLog.LogTopic = log.LogTopic;
//log 可能映射了新的表名
newLog.MapNewTableName(log.GetTableName());
bool result = Transaction(ctx => {
query.Insert(newLog);
//解析得到真正的命令参数信息
var paras = log.ParseParameter(this.CurrentDataBase);
int count = this.CurrentDataBase.ExecuteNonQuery(log.CommandText, log.CommandType, paras);
//可以在此处考虑引发处理后事件
if (AfterReplications != null)
{
AfterReplications(this, new ReplicationEventArgs(log, count));
}
}, out errorMessage);
this.ErrorMessage = errorMessage;
this.CurrentStatus = result ? ReplicationStatus.Succeed : ReplicationStatus.Error;
return(result);
}
}
/// <summary>
/// 以一个日志对象初始化本类
/// </summary>
/// <param name="log"></param>
/// <param name="affected"></param>
public ReplicationEventArgs(MyCommandLogEntity log, int affected)
{
this.Log = log;
this.AffectedCount = affected;
}
/// <summary>
/// 按照顺序读取事务日志并进行处理
/// </summary>
/// <param name="pageSize">每次要读取的日志页大小</param>
/// <param name="func">处理日志的自定义方法，如果返回假则不再继续读取处理</param>
/// <param name="partLogName">分部的日志消息表名字,可以为空</param>
/// <returns>返回已经读取的记录数量</returns>
public int ReadLog(int pageSize, Func <List <MyCommandLogEntity>, bool> func, string partLogName = null)
{
int pageNumber = 1;
int readCount = 0;
int allCount = 0;
//先查询出所有记录数和第一页的数据
MyCommandLogEntity log = new MyCommandLogEntity();
if (!string.IsNullOrEmpty(partLogName))
{
log.MapNewTableName(log.GetTableName() + "_" + partLogName);
}
var oql = OQL.From(log)
.Select()
.OrderBy(o => o.Asc(log.CommandID))
.END
.Limit(pageSize, pageNumber);
oql.PageWithAllRecordCount = 0;
var list = EntityQuery <MyCommandLogEntity> .QueryList(oql, this.CurrentDataBase);
allCount = oql.PageWithAllRecordCount;
while (list.Count > 0)
{
readCount += list.Count;
ReadLogEventArgs args = new ReadLogEventArgs(allCount, readCount, list);
if (OnReadLog != null)
{
OnReadLog(this, args);
}
if (!func(list))
{
break;
}
if (list.Count < pageSize)
{
break;
}
pageNumber++;
/*
* //使用GOQL简化查询
* list = OQL.From<MyCommandLogEntity>()
* .Select()
* .OrderBy((o, p) => o.Asc(p.CommandID))
* .Limit(pageSize, pageNumber,allCount)
* .ToList(this.CurrentDataBase);
*/
//因为日志可能分表，需要修改下面的方式:
var oql1 = OQL.From(log)
.Select()
.OrderBy(o => o.Asc(log.CommandID))
.END
.Limit(pageSize, pageNumber);
oql1.PageWithAllRecordCount = allCount;
list = EntityQuery <MyCommandLogEntity> .QueryList(oql1, this.CurrentDataBase);
}
return(readCount);
}
/// <summary>
/// 默认构造函数
/// </summary>
public TransactionLogHandle()
{
logEntity = new MyCommandLogEntity();
enable = true;
}
