/// <summary>
/// 创建通过主键删除的语句片段。
/// </summary>
/// <param name="data">内容对象。</param>
/// <param name="table">删除表的元数据。</param>
/// <param name="name">指定名称。</param>
/// <returns>语句片段。</returns>
internal static DeleteFragment DeleteByKeys(this ContentBase data, TableMetadata table, DbName name = null)
{
var delete = new DeleteFragment(data.GenerateContext, table, name);
delete.Where = delete.Target.JoinCondition(data.CommitObject,
data.UnionConcurrencyMembers(table, table.Keys));
return(delete);
}
internal static InsertValueFragment InsertTemptable(this ContentBase data, TemporaryTableFragment temptable, IEnumerable <CommitMember> members)
{
var context = data.GenerateContext;
var insert = new InsertValueFragment(context, temptable, data.CommitObject, data.Items);
data.CommitObject.Parent = insert;
members.ForEach(member => SetCommitMember(insert, member));
return(insert);
}
internal static InsertValueFragment InsertUnit(this ContentBase data, CommitIdentityUnit unit, DbName name = null)
{
var context = data.GenerateContext;
var target = new TableFragment(context, unit.Table, name);
var insert = new InsertValueFragment(context, target, data.CommitObject, data.Items);
data.CommitObject.Parent = insert;
unit.Members.ForEach(member => SetCommitMember(insert, member));
return(insert);
}
internal static UpdateFragment UpdateByTemptable(this ContentBase data, CommitUnitBase unit, SourceFragment current, DbName name = null)
{
var context = data.GenerateContext;
var metadata = unit.Table;
var update = new UpdateFragment(context, metadata, name);
update.AddSource(update.Target, current);
data.SetCommitMembers(update, unit, current);
update.Target.Join(current, data.UnionConcurrencyMembers(metadata, metadata.Keys));
return(update);
}
internal static UpdateFragment UpdateByKeys(this ContentBase data, CommitUnitBase unit, DbName name = null)
{
var context = data.GenerateContext;
var metadata = unit.Table;
var update = new UpdateFragment(context, metadata, name);
data.CommitObject.Parent = update;
data.SetCommitMembers(update, unit);
update.Where = update.Target.JoinCondition(data.CommitObject, data.UnionConcurrencyMembers(metadata, metadata.Keys));
return(update);
}
/// <summary>
/// 创建通过临时博删除的语句片段。
/// </summary>
/// <param name="data">内容对象。</param>
/// <param name="metadata">删除表的元数据。</param>
/// <param name="temptable">临时表。</param>
/// <param name="name">指定名称。</param>
/// <returns>语句片段。</returns>
internal static DeleteFragment DeleteByTemptable(this ContentBase data
, TableMetadata metadata, TemporaryTableFragment temptable, DbName name = null)
{
var context = data.GenerateContext;
var filterMembers = data.UnionConcurrencyMembers(metadata, metadata.Keys);
var delete = new DeleteFragment(context, metadata);
var current = delete.Target;
var currenttemptable = new TemporaryTableFragment(context, filterMembers, temptable.Name);
delete.AddSource(currenttemptable);
current.Join(currenttemptable, filterMembers);
return(delete);
}
/// <summary>
/// 创建通过 IN 主键删除的语句片段。
/// </summary>
/// <param name="data">内容对象。</param>
/// <param name="table">删除表的元数据。</param>
/// <param name="key">主键元数据。</param>
/// <param name="values">值列表对象。</param>
/// <param name="name">指定名称。</param>
/// <returns>语句片段。</returns>
internal static DeleteFragment DeleteInKey(this ContentBase data, TableMetadata table
, ColumnMetadata key, ValueListFragment values, DbName name = null)
{
var context = data.GenerateContext;
var delete = new DeleteFragment(context, table, data.TargetName);
var keyMember = delete.Target.GetMember(key);
delete.Where = new ScalarFragment(context, values, keyMember)
{
Function = SupportMembers.Enumerable.Contains
};
return(delete);
}
internal static InsertFragment InsertTemptable(this ContentBase data, TemporaryTableFragment temptable, CommitKeyUnit unit, DbName name = null)
{
var members = unit.Keys.Concat(unit.Members).Select(a => a.Metadata);
var context = data.GenerateContext;
var table = new TableFragment(context, unit.Table, name);
var select = new SelectFragment(context, temptable);
var current = new InsertFragment(context, table, select);
foreach (var member in members)
{
select.CreateMember(null, temptable.GetMember(member));
current.CreateMember(null, member);
}
return(current);
}
private static void SetCommitMembers(this ContentBase data, UpdateFragment update, CommitUnitBase unit, ISourceFragment source = null)
{
source = source ?? data.CommitObject;
foreach (var member in unit.Members)
{
switch (member.ValueType)
{
case ECommitValueType.Constant:
update.SetValue(member.Metadata, source.GetMember(member.Metadata));
break;
case ECommitValueType.Expression:
var exp = (CommitExpressionMember)member;
update.SetValue(member.Metadata, update.CreateExpression(exp.Expression));
break;
}
}
}
