private string TranslateOneToMany(string functionName, MemberExpression memberExpression, LambdaExpression fieldExpression, LambdaExpression filterExpression)
{
if (!string.IsNullOrEmpty(TranslateMember(memberExpression))) // this shouldn't return any SQL
{
throw new SqlExpressionTranslatorException(memberExpression.ToString());
}
var relation = GetRelation(memberExpression.Expression, memberExpression.Member.Name);
if (relation == null)
{
throw new SqlExpressionTranslatorException(memberExpression.ToString());
}
if (fieldExpression != null && filterExpression != null && fieldExpression.Parameters[0] != filterExpression.Parameters[0])
{
throw new SqlExpressionTranslatorException(null);
}
var iterator = fieldExpression != null ? fieldExpression.Parameters[0] : filterExpression != null ? filterExpression.Parameters[0] : Expression.Parameter(relation.ElementType);
LambdaExpression relationExpression = CreateToManyFilterExpression(relation, memberExpression.Expression, filterExpression, iterator);
var template = _toManyTemplates[functionName];
if (template == null)
{
throw new NotSupportedException(functionName);
}
var alias = SqlNameGenerator.NextTableAlias();
_metaData[iterator] = new ExpressionMetaData {
Iterator = iterator, Relation = relation, Schema = relation.ForeignSchema
};
_relationAliases[iterator] = new Dictionary <object, string> {
{ relation, alias }
};
_subQueries.Push(new SubQuery());
string sqlFields = Translate(fieldExpression);
string sqlWhere = Translate(relationExpression);
string sqlJoins = (Joins.Count > 0) ? string.Join(" ", Joins.Select(join => join.ToSql(_sqlDialect))) : null;
_subQueries.Pop();
return(string.Format(template,
sqlFields,
_sqlDialect.QuoteTable(relation.ForeignSchema.MappedName) + " " + alias, sqlJoins ?? "",
sqlWhere
));
}
public override void Purge(TableSchema schema)
{
var tableName = SqlDialect.QuoteTable(schema.MappedName);
ExecuteSql("DELETE FROM " + tableName, null);
if (SqlQueryScalar("select name from sqlite_master where name='sqlite_sequence'", null).Any())
{
ExecuteSql("delete from sqlite_sequence where name=@name", QueryParameterCollection.FromObject(new { name = schema.MappedName }));
}
}