internal static List <PrefetchField> GetPrefetchFieldsOne(CSTable table, List <string> fieldList, List <string> aliasList, CSJoinList joinList, string[] prefetchPaths)
{
List <PrefetchField> prefetchFields = new List <PrefetchField>();
foreach (CSSchemaField schemaField in table.Schema.Fields)
{
bool prefetch = schemaField.Prefetch;
string fieldName = schemaField.Name;
prefetch |= (prefetchPaths != null && prefetchPaths.Any(s =>
{
if (s.IndexOf('.') > 0)
{
s = s.Substring(0, s.IndexOf('.'));
}
return(s == fieldName);
}));
if (schemaField.Relation != null && schemaField.Relation.RelationType == CSSchemaRelationType.ManyToOne && prefetch)
{
CSJoin join = new CSJoin(schemaField.Relation, table.TableAlias);
joinList.Add(join);
PrefetchField prefetchField = new PrefetchField();
prefetchField.SchemaField = schemaField;
foreach (string columnName in schemaField.Relation.ForeignSchema.ColumnsToRead)
{
string alias = CSNameGenerator.NextFieldAlias;
fieldList.Add(join.RightAlias + "." + columnName);
aliasList.Add(alias);
prefetchField.AliasMap[alias] = columnName;
}
prefetchFields.Add(prefetchField);
}
}
return(prefetchFields);
}
private static object EvalVariable(string var, QueryExpression parentQuery)
{
Match match = _regexVar.Match(var);
if (!match.Success)
{
throw new CSExpressionException("Object [" + var + "] is unknown");
}
List <string> fieldNames = new List <string>();
foreach (Capture capture in match.Groups["Object"].Captures)
{
fieldNames.Add(capture.Value);
}
QueryExpression subExpression = null;
CSTable currentTable = parentQuery.Table;
string fieldName = null;
for (int i = 0; i < fieldNames.Count; i++)
{
bool isLast = (i == fieldNames.Count - 1);
CSJoin currentJoin = null;
CSSchemaField schemaField = currentTable.Schema.Fields[fieldNames[i]];
if (schemaField == null)
{
throw new CSException("Error in expression. [" + fieldNames[i] + "] is not a valid field name");
}
if (schemaField.Relation != null)
{
switch (schemaField.Relation.RelationType)
{
case CSSchemaRelationType.OneToMany:
{
if (subExpression != null)
{
throw new CSExpressionException("Error in expression [" + var + "]: Multiple *ToMany relations");
}
subExpression = new QueryExpression(schemaField.Relation.ForeignSchema);
subExpression.Joins = new CSJoinList();
subExpression.Expression = currentTable.TableAlias + "." + currentTable.Schema.DB.QuoteField(schemaField.Relation.LocalKey) + "=" + subExpression.Table.TableAlias + "." + currentTable.Schema.DB.QuoteField(schemaField.Relation.ForeignKey);
}
break;
case CSSchemaRelationType.ManyToMany:
{
if (subExpression != null)
{
throw new CSExpressionException("Error in expression [" + var + "]: Multiple *ToMany relations");
}
subExpression = new QueryExpression(schemaField.Relation.ForeignSchema);
subExpression.Joins = new CSJoinList();
currentJoin = new CSJoin();
currentJoin.LeftSchema = schemaField.Relation.ForeignSchema;
currentJoin.LeftTable = subExpression.Table.TableName;
currentJoin.LeftAlias = subExpression.Table.TableAlias;
currentJoin.RightTable = schemaField.Relation.LinkTable;
currentJoin.RightAlias = CSNameGenerator.NextTableAlias;
currentJoin.LeftColumn = schemaField.Relation.ForeignKey;
currentJoin.RightColumn = schemaField.Relation.ForeignLinkKey;
currentJoin.Type = CSJoinType.Inner;
subExpression.Joins.Add(currentJoin);
subExpression.Expression = currentJoin.RightAlias + "." + currentTable.Schema.DB.QuoteField(schemaField.Relation.LocalLinkKey) + "=" + currentTable.TableAlias + "." + currentTable.Schema.DB.QuoteField(schemaField.Relation.LocalKey);
currentJoin = null;
}
break;
case CSSchemaRelationType.ManyToOne:
{
if (!isLast)
{
if (subExpression != null) // meaning we already encountered a *toMany relation
{
currentJoin = new CSJoin(schemaField.Relation, subExpression.Table.TableAlias);
if (subExpression.Joins.Contains(currentJoin))
{
currentJoin = subExpression.Joins.GetExistingJoin(currentJoin);
}
else
{
subExpression.Joins.Add(currentJoin);
}
}
else
{
currentJoin = new CSJoin(schemaField.Relation, currentTable.TableAlias);
if (parentQuery.Joins.Contains(currentJoin))
{
currentJoin = parentQuery.Joins.GetExistingJoin(currentJoin);
}
else
{
parentQuery.Joins.Add(currentJoin);
}
}
}
}
break;
}
if (!isLast)
{
if (currentJoin != null)
{
currentTable = new CSTable(schemaField.Relation.ForeignSchema, currentJoin.RightAlias);
}
else
{
if (subExpression != null)
{
currentTable = new CSTable(schemaField.Relation.ForeignSchema, subExpression.Table.TableAlias);
}
else
{
currentTable = new CSTable(schemaField.Relation.ForeignSchema);
}
}
}
else
{
fieldName = currentTable.Schema.DB.QuoteField(currentTable.TableAlias + "." + schemaField.Relation.LocalKey);
}
}
else
{
fieldName = currentTable.Schema.DB.QuoteField(currentTable.TableAlias + "." + schemaField.MappedColumn.Name);
}
}
if (subExpression != null)
{
subExpression.FieldName = fieldName;
return(subExpression);
}
else
{
//if (fieldName != null)
return(fieldName);
}
}