public virtual string JoinSql(SqlJoinDefinition join)
{
return string.Format("{0} join {1} {2} on {3}={4}",
join.Type == SqlJoinType.Inner ? "inner" : "left outer",
QuoteTable(@join.Right.Schema.MappedName),
join.Right.Alias,
QuoteField(join.Left.Alias + "." + @join.Left.Field.MappedName),
QuoteField(join.Right.Alias + "." + @join.Right.Field.MappedName)
);
}
private string ProcessRelation(Expression fullExpression, Expression leftExpression, string memberName)
{
var parentMetaData = _metaData[leftExpression];
if (parentMetaData != null)
{
if (_metaData.ContainsKey(fullExpression))
return null; // relation already visited
var iterator = GetRootIterator(parentMetaData.Iterator);
var relation = parentMetaData.Schema.Relations[memberName];
var leftAlias = _relationAliases[iterator][parentMetaData.Key];
if (relation != null && relation.IsToOne)
{
if (!_relationAliases[iterator].ContainsKey(relation))
{
var sqlJoin = new SqlJoinDefinition(
new SqlJoinPart(parentMetaData.Schema, relation.LocalField, leftAlias),
new SqlJoinPart(relation.ForeignSchema, relation.ForeignField, SqlNameGenerator.NextTableAlias())
);
CurrentQuery.Joins.Add(sqlJoin);
_relationAliases[iterator][relation] = sqlJoin.Right.Alias;
}
_metaData[fullExpression] = new ExpressionMetaData { Iterator = iterator, Relation = relation, Schema = relation.ForeignSchema };
}
else if (relation == null)
{
return leftAlias + "." + memberName;
}
}
return null;
}