/// <summary>
/// 贪婪加载某个属性
/// </summary>
/// <param name="property">需要贪婪加载的托管属性。可以是一个引用属性，也可以是一个组合子属性。</param>
private void EagerLoad(ConcreteProperty property)
{
if (this.EagerLoadOptions == null)
{
this.EagerLoadOptions = new EagerLoadOptions();
}
this.EagerLoadOptions.CoreList.Add(property);
}
public override void RefreshRedundancy(ConcreteProperty redundancy)
{
/*********************** 代码块解释 *********************************
* http://blog.csdn.net/peng790/article/details/6585202
*
* 假定场景是：
* D(CRef,AName) -> C(BRef) -> B(ARef) -> A(Name);
* 则对应生成的 SQL 是：
* update D set AName = @AName where CId in (
* select id from C where BId in (
* select id from B where AId = @AId
* )
* )
* 如果 B、C 表也有冗余属性，对应的 SQL 则是：
* update B Set AName = @AName where AId = @AId
* update C set AName = @AName where BId in (
* select id from B where AId = @AId
* )
*
**********************************************************************/
//update B set AName = A.Name FROM A WHERE A.ID = b.AId
//update C set AName = A.Name FROM A INNER JOIN B ON A.Id = B.AId WHERE B.Id = C.BId
//update D set AName = A.Name FROM A INNER JOIN B ON A.Id = B.AId INNER JOIN C ON B.Id = c.BId WHERE C.Id = D.CId
////准备所有用到的 DbTable
//var table = RdbTableFinder.TableFor(path.Redundancy.Owner);
//var refTables = new RefPropertyTable[refPathes.Count];
//for (int i = 0, c = refPathes.Count; i < c; i++)
//{
// var refProperty = refPathes[i];
// var refTable = RdbTableFinder.TableFor(refProperty.Owner);
// if (refTable == null)
// {
// ORMHelper.ThrowBasePropertyNotMappedException(refProperty.Name, refProperty.Owner);
// }
// refTables[i] = new RefPropertyTable
// {
// RefProperty = refProperty,
// OwnerTable = refTable
// };
//}
//var sql = new ConditionalSql();
////SQL: UPDATE D SET AName = {0} WHERE
//sql.Append("UPDATE ").AppendQuoteName(table)
// .Append(" SET ").AppendQuote(table, table.Translate(redundancy.Property))
// .Append(" = ").AppendParameter(newValue).Append(" WHERE ");
//int quoteNeeded = 0;
//if (refTables.Length > 1)
//{
// //中间的都生成 Where XX in
// var inWherePathes = refTables.Take(refTables.Length - 1).ToArray();
// for (int i = 0; i < inWherePathes.Length; i++)
// {
// var inRef = inWherePathes[i];
// //SQL: CId In (
// sql.AppendQuote(table, inRef.OwnerTable.Translate(inRef.RefProperty.Property))
// .Append(" IN (").AppendLine();
// quoteNeeded++;
// var nextRef = refTables[i + 1];
// //SQL: SELECT Id FROM C WHERE
// var nextRefOwnerTable = nextRef.OwnerTable;
// sql.Append(" SELECT ").AppendQuote(nextRefOwnerTable, nextRefOwnerTable.PKColumn.Name)
// .Append(" FROM ").AppendQuoteName(nextRefOwnerTable)
// .Append(" WHERE ");
// }
//}
////最后一个，生成SQL: BId = {1}
//var lastRef = refTables[refTables.Length - 1];
//sql.AppendQuote(table, lastRef.OwnerTable.Translate(lastRef.RefProperty.Property))
// .Append(" = ").AppendParameter(lastRefId);
//while (quoteNeeded > 0)
//{
// sql.AppendLine(")");
// quoteNeeded--;
//}
////执行最终的 SQL 语句
//using (var dba = _dataProvider.CreateDbAccesser())
//{
// dba.ExecuteText(sql, sql.Parameters);
//}
}
protected override void UpdateRedundancy(Entity entity, ConcreteProperty redundancy, object newValue, IList<ConcreteProperty> refPathes, object lastRefId)
{
/*********************** 代码块解释 *********************************
*
* 假定场景是：
* refPathes: D(CRef,AName) -> C(BRef) -> B(ARef)，
* lastRefId: AId。（B.ARef 是最后一个引用属性）
* 则对应生成的 SQL 是：
* update D set AName = @AName where CId in (
* select id from C where BId in (
* select id from B where AId = @AId
* )
* )
* 如果 B、C 表也有冗余属性，对应的 SQL 则是：
* update B Set AName = @AName where AId = @BId
* update C set AName = @AName where BId in (
* select id from B where AId = @AId
* )
*
**********************************************************************/
//准备所有用到的 DbTable
var table = RdbTableFinder.TableFor(redundancy.Owner);
var refTables = new RefPropertyTable[refPathes.Count];
for (int i = 0, c = refPathes.Count; i < c; i++)
{
var refProperty = refPathes[i];
var refTable = RdbTableFinder.TableFor(refProperty.Owner);
if (refTable == null)
{
ORMHelper.ThrowBasePropertyNotMappedException(refProperty.Name, refProperty.Owner);
}
refTables[i] = new RefPropertyTable
{
RefProperty = refProperty,
OwnerTable = refTable
};
}
var sql = new ConditionalSql();
//SQL: UPDATE D SET AName = {0} WHERE
sql.Append("UPDATE ").AppendQuoteName(table)
.Append(" SET ").AppendQuote(table, table.Translate(redundancy.Property))
.Append(" = ").AppendParameter(newValue).Append(" WHERE ");
int quoteNeeded = 0;
if (refTables.Length > 1)
{
//中间的都生成 Where XX in
var inWherePathes = refTables.Take(refTables.Length - 1).ToArray();
for (int i = 0; i < inWherePathes.Length; i++)
{
var inRef = inWherePathes[i];
//SQL: CId In (
sql.AppendQuote(table, inRef.OwnerTable.Translate(inRef.RefProperty.Property))
.Append(" IN (").AppendLine();
quoteNeeded++;
var nextRef = refTables[i + 1];
//SQL: SELECT Id FROM C WHERE
var nextRefOwnerTable = nextRef.OwnerTable;
sql.Append(" SELECT ").AppendQuote(nextRefOwnerTable, nextRefOwnerTable.PKColumn.Name)
.Append(" FROM ").AppendQuoteName(nextRefOwnerTable)
.Append(" WHERE ");
}
}
//最后一个，生成SQL: BId = {1}
var lastRef = refTables[refTables.Length - 1];
sql.AppendQuote(table, lastRef.OwnerTable.Translate(lastRef.RefProperty.Property))
.Append(" = ").AppendParameter(lastRefId);
while (quoteNeeded > 0)
{
sql.AppendLine(")");
quoteNeeded--;
}
//执行最终的 SQL 语句
using (var dba = _dataProvider.CreateDbAccesser())
{
dba.ExecuteText(sql, sql.Parameters);
}
}
/// <summary> /// 更新某个冗余属性 /// </summary> /// <param name="entity">The entity.</param> /// <param name="redundancy">更新指定的冗余属性</param> /// <param name="newValue">冗余属性的新值</param> /// <param name="refPathes">从冗余属性声明类型开始的一个引用属性集合， /// 将会为这个集合路径生成更新的 Where 条件。</param> /// <param name="lastRefId">引用路径中最后一个引用属性对应的值。这个值将会作为 Where 条件的值。</param> protected abstract void UpdateRedundancy(Entity entity, ConcreteProperty redundancy, object newValue, IList<ConcreteProperty> refPathes, object lastRefId);