private TableIdentifier Join(Aliaser aliaser, UpdateStatement statement, SchemaMember schema)
{
if (schema == null || schema.Token.Property.IsSimplex)
{
return(null);
}
//获取关联的源
ISource source = schema.Parent == null ?
statement.Table :
statement.From.Get(schema.Path);
//第一步：处理模式成员所在的继承实体的关联
if (schema.Ancestors != null)
{
foreach (var ancestor in schema.Ancestors)
{
source = statement.Join(aliaser, source, ancestor, schema.FullPath);
}
}
//第二步：处理模式成员（导航属性）的关联
var join = statement.Join(aliaser, source, schema);
var target = (TableIdentifier)join.Target;
statement.Tables.Add(target);
//返回关联的目标表
return(target);
}
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);
}
}
private void GenerateSortings(Aliaser aliaser, SelectStatement statement, TableIdentifier origin, Sorting[] sortings)
{
if (sortings == null || sortings.Length == 0)
{
return;
}
statement.OrderBy = new OrderByClause();
foreach (var sorting in sortings)
{
if (string.IsNullOrEmpty(sorting.Name))
{
continue;
}
var source = statement.From(origin, sorting.Name, aliaser, null, out var property);
var simplex = property.IsSimplex ?
(IDataEntitySimplexProperty)property :
throw new DataException($"The specified '{property.Entity.Name}.{property.Name}' is a composite(navigation) property that is not sortable.");
if (simplex.IsPrimaryKey || simplex.Sortable)
{
statement.OrderBy.Add(source.CreateField(property), sorting.Mode);
}
else
{
throw new DataException($"The specified '{property.Entity.Name}.{property.Name}' property is not sortable and must be enabled for sorting before it can be sorted.");
}
}
}
private DeleteStatement BuildInherit(Aliaser aliaser, DeleteStatement master, IDataEntity entity)
{
var statement = new DeleteStatement(entity);
var reference = master.Returning.Table.Identifier();
if (entity.Key.Length == 1)
{
var select = new SelectStatement(reference);
select.Select.Members.Add(reference.CreateField(master.Returning.Table.Fields.First().Name));
statement.Where = Expression.In(statement.Table.CreateField(entity.Key[0]), select);
}
else
{
var join = new JoinClause(TEMPORARY_ALIAS, reference, JoinType.Inner);
foreach (var key in entity.Key)
{
join.Conditions.Add(
Expression.Equal(
statement.Table.CreateField(key),
reference.CreateField(key)));
}
statement.From.Add(join);
}
master.Slaves.Add(statement);
return(statement);
}
private void GenerateGrouping(Aliaser aliaser, SelectStatement statement, Grouping grouping)
{
if (grouping == null)
{
return;
}
if (grouping.Keys != null && grouping.Keys.Length > 0)
{
//创建分组子句
statement.GroupBy = new GroupByClause();
foreach (var key in grouping.Keys)
{
var source = statement.From(key.Name, aliaser, null, out var property);
if (property.IsComplex)
{
throw new DataException($"The grouping key '{property.Name}' can not be a complex property.");
}
statement.GroupBy.Keys.Add(source.CreateField(property));
statement.Select.Members.Add(source.CreateField(property.GetFieldName(out var alias), key.Alias ?? alias));
}
if (grouping.Filter != null)
{
statement.GroupBy.Having = statement.Where(grouping.Filter, aliaser, false);
}
}
foreach (var aggregate in grouping.Aggregates)
{
if (string.IsNullOrEmpty(aggregate.Name) || aggregate.Name == "*")
{
statement.Select.Members.Add(
new AggregateExpression(aggregate.Function, aggregate.Distinct, Expression.Constant(0))
{
Alias = string.IsNullOrEmpty(aggregate.Alias) ? aggregate.Function.ToString() : aggregate.Alias
});
}
else
{
var source = statement.From(aggregate.Name, aliaser, null, out var property);
if (property.IsComplex)
{
throw new DataException($"The field '{property.Name}' of aggregate function can not be a complex property.");
}
statement.Select.Members.Add(
new AggregateExpression(aggregate.Function, aggregate.Distinct, source.CreateField(property))
{
Alias = string.IsNullOrEmpty(aggregate.Alias) ? aggregate.Name : aggregate.Alias
});
}
}
}
/// <inheritdoc />
public JoinClause Join(Aliaser aliaser, ISource source, SchemaMember schema)
{
if (schema.Token.Property.IsSimplex)
{
return(null);
}
return(this.Join(aliaser, source, (IDataEntityComplexProperty)schema.Token.Property, schema.FullPath));
}
/// <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);
}
private DeleteStatement BuildSlave(Aliaser aliaser, DeleteStatement master, SchemaMember schema)
{
var complex = (IDataEntityComplexProperty)schema.Token.Property;
var statement = new DeleteStatement(complex.Foreign);
var reference = master.Returning.Table.Identifier();
if (complex.Links.Length == 1)
{
var select = new SelectStatement(reference);
select.Select.Members.Add(reference.CreateField(complex.Links[0].GetAnchors().Last()));
statement.Where = Expression.In(statement.Table.CreateField(complex.Links[0].Foreign), select);
}
else
{
var join = new JoinClause(TEMPORARY_ALIAS, reference, JoinType.Inner);
foreach (var link in complex.Links)
{
var anchor = link.GetAnchors().Last();
join.Conditions.Add(
Expression.Equal(
statement.Table.CreateField(link.Foreign),
reference.CreateField(anchor.Name)));
}
statement.From.Add(join);
}
var super = statement.Entity.GetBaseEntity();
if (super != null || schema.HasChildren)
{
this.BuildReturning(aliaser, statement, schema.Children);
}
else
{
master.Slaves.Add(statement);
}
return(statement);
}
private void Join(Aliaser aliaser, DeleteStatement statement, TableIdentifier table, SchemaMember schema)
{
if (table == null || schema == null || schema.Token.Property.IsSimplex)
{
return;
}
//不可变复合属性不支持任何写操作，即在删除操作中不能包含不可变复合属性
if (schema.Token.Property.Immutable)
{
throw new DataException($"The '{schema.FullPath}' is an immutable complex(navigation) property and does not support the delete operation.");
}
var join = statement.Join(aliaser, table, schema);
var target = (TableIdentifier)join.Target;
statement.Tables.Add(target);
//生成当前导航属性表的继承链关联集
var joins = this.Join(aliaser, statement, target, schema.FullPath);
if (schema.HasChildren)
{
foreach (var child in schema.Children)
{
if (joins != null)
{
join = joins.FirstOrDefault(j => ((TableIdentifier)j.Target).Entity == child.Token.Property.Entity);
if (join != null)
{
target = (TableIdentifier)join.Target;
}
}
this.Join(aliaser, statement, target, child);
}
}
}
/// <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);
}
private void GenerateSchema(Aliaser aliaser, SelectStatement statement, ISource origin, SchemaMember member)
{
if (member.Ancestors != null)
{
foreach (var ancestor in member.Ancestors)
{
origin = statement.Join(aliaser, origin, ancestor, member.Path);
}
}
if (member.Token.Property.IsComplex)
{
var complex = (IDataEntityComplexProperty)member.Token.Property;
//一对多的导航属性对应一个新语句（新语句别名即为该导航属性的全称）
if (complex.Multiplicity == DataAssociationMultiplicity.Many)
{
var slave = new SelectStatement(complex.Foreign, member.FullPath)
{
Paging = member.Paging
};
var table = slave.Table;
if (complex.ForeignProperty != null)
{
if (complex.ForeignProperty.IsSimplex)
{
slave.Select.Members.Add(slave.Table.CreateField(complex.ForeignProperty));
}
else
{
table = (TableIdentifier)slave.Join(aliaser, slave.Table, (IDataEntityComplexProperty)complex.ForeignProperty).Target;
}
}
statement.Slaves.Add(slave);
//为一对多的导航属性增加必须的链接字段及对应的条件参数
foreach (var link in complex.Links)
{
foreach (var anchor in link.GetAnchors())
{
if (anchor.IsComplex)
{
origin = statement.Join(aliaser, origin, (IDataEntityComplexProperty)anchor);
}
else
{
var principalField = origin.CreateField(anchor);
principalField.Alias = "$" + member.FullPath + ":" + anchor.Name;
statement.Select.Members.Add(principalField);
var foreignField = slave.Table.CreateField(link.ForeignKey);
foreignField.Alias = null;
if (slave.Where == null)
{
slave.Where = Expression.Equal(foreignField, slave.Parameters.Add(anchor.Name, link.ForeignKey.Type));
}
else
{
slave.Where = Expression.AndAlso(slave.Where,
Expression.Equal(foreignField, slave.Parameters.Add(anchor.Name, link.ForeignKey.Type)));
}
}
}
}
//为导航属性增加约束过滤条件
if (complex.HasConstraints())
{
foreach (var constraint in complex.Constraints)
{
slave.Where = Expression.AndAlso(slave.Where,
Expression.Equal(
table.CreateField(constraint.Name),
complex.GetConstraintValue(constraint)));
}
}
if (member.Sortings != null)
{
this.GenerateSortings(aliaser, slave, table, member.Sortings);
}
if (member.HasChildren)
{
foreach (var child in member.Children)
{
this.GenerateSchema(aliaser, slave, table, child);
}
}
return;
}
//对于一对一的导航属性，创建其关联子句即可
origin = statement.Join(aliaser, origin, complex, member.FullPath);
//确保导航属性的外链表的主键都在
if (member.HasChildren)
{
foreach (var key in complex.Foreign.Key)
{
if (!member.Children.Contains(key.Name))
{
member.Append(new SchemaMember(key));
}
}
}
}
else
{
var field = origin.CreateField(member.Token.Property);
//只有数据模式元素是导航子元素以及与当前语句的别名不同（相同则表示为同级），才需要指定字段引用的别名
if (member.Parent != null && !string.Equals(member.Path, statement.Alias, StringComparison.OrdinalIgnoreCase))
{
if (string.IsNullOrEmpty(statement.Alias))
{
field.Alias = member.FullPath;
}
else
{
field.Alias = Zongsoft.Common.StringExtension.TrimStart(member.FullPath, statement.Alias + ".", StringComparison.OrdinalIgnoreCase);
}
}
statement.Select.Members.Add(field);
}
if (member.HasChildren)
{
foreach (var child in member.Children)
{
this.GenerateSchema(aliaser, statement, origin, child);
}
}
}
private void BuildReturning(Aliaser aliaser, DeleteStatement statement, IEnumerable <SchemaMember> schemas)
{
statement.Returning = new ReturningClause(TableDefinition.Temporary());
foreach (var key in statement.Entity.Key)
{
statement.Returning.Table.Field(key);
statement.Returning.Append(statement.Table.CreateField(key), ReturningClause.ReturningMode.Deleted);
}
var super = statement.Entity.GetBaseEntity();
while (super != null)
{
this.BuildInherit(aliaser, statement, super);
super = super.GetBaseEntity();
}
foreach (var schema in schemas)
{
if (schema.Token.Property.IsSimplex)
{
continue;
}
var complex = (IDataEntityComplexProperty)schema.Token.Property;
ISource src = complex.Entity == statement.Entity ?
statement.Table :
statement.Join(aliaser, statement.Table, complex.Entity);
foreach (var link in complex.Links)
{
var anchors = link.GetAnchors();
if (anchors.Length > 1)
{
continue;
}
ISource source = statement.Table;
foreach (var anchor in link.GetAnchors())
{
if (anchor.IsComplex)
{
source = statement.Join(aliaser, source, (IDataEntityComplexProperty)anchor);
}
else
{
//某些导航属性可能与主键相同，表定义的字段定义方法（TableDefinition.Field(...)）可避免同名字段的重复定义
if (statement.Returning.Table.Field((IDataEntitySimplexProperty)anchor) != null)
{
statement.Returning.Append(src.CreateField(anchor.Name), ReturningClause.ReturningMode.Deleted);
}
}
}
}
this.BuildSlave(aliaser, statement, schema);
}
}