private IEnumerable <JoinClause> Join(Aliaser aliaser, DeleteStatement statement, TableIdentifier table, string fullPath = null)
{
if (table == null || table.Entity == null)
{
yield break;
}
var super = table.Entity.GetBaseEntity();
while (super != null)
{
var clause = JoinClause.Create(table,
fullPath,
name => statement.From.TryGet(name, out var join) ? (JoinClause)join : null,
entity => new TableIdentifier(entity, aliaser.Generate()));
if (!statement.From.Contains(clause))
{
statement.From.Add(clause);
statement.Tables.Add((TableIdentifier)clause.Target);
}
super = super.GetBaseEntity();
yield return(clause);
}
}
/// <inheritdoc />
public JoinClause Join(Aliaser aliaser, ISource source, IDataEntity target, string fullPath = null)
{
var clause = JoinClause.Create(source,
target,
fullPath,
name => this.From.TryGet(name, out var join) ? (JoinClause)join : null,
entity => new TableIdentifier(entity, aliaser.Generate()));
if (!this.From.Contains(clause))
{
this.From.Add(clause);
}
return(clause);
}
/// <inheritdoc />
public JoinClause Join(Aliaser aliaser, ISource source, IDataEntityComplexProperty complex, string fullPath = null)
{
var joins = JoinClause.Create(source,
complex,
fullPath,
name => this.From.TryGet(name, out var join) ? (JoinClause)join : null,
entity => new TableIdentifier(entity, aliaser.Generate()));
JoinClause last = null;
foreach (var join in joins)
{
if (!this.From.Contains(join))
{
this.From.Add(join);
}
last = join;
}
//返回最后一个Join子句
return(last);
}