public ProjectionExpression UpdateSelect(ProjectionExpression projection, Expression selectExpression)
{
//get the lambda expression of the select method
var lambda = (LambdaExpression)selectExpression.StripQuotes();
//if the lambda, is the identity lamda, simply return
if (lambda.IsIdentityLambda())
return projection;
//map the source argument of the lambda expression to the existing projection
Map.Add(lambda.Parameters[0], projection.Projection);
//get the new projection
var newProjection = Visit(lambda.Body);
//check if projection is actually changed
if (newProjection == lambda.Body)
return projection;
//get used columns
IEnumerable<SelectorExpression> columns = new ColumnFinder().FindColumns(newProjection);
SelectStatementExpression select = projection.Select;
var newSelect = new SelectStatementExpression(typeof(IEnumerable<>).MakeGenericType(newProjection.Type),
new SelectClauseExpression(columns.ToArray(),
select.SelectClause.Distinct),
select.TableName,
select.WhereClause,
select.OrderBy,
select.Limit,
select.AllowFiltering);
return new ProjectionExpression(newSelect, newProjection, projection.Aggregator, false, projection.Consistency, projection.PageSize);
}
public TransactionController(ICommandsBus bus,
TransactionReader transactionReader,
ColumnFinder columnFinder,
BankTransactionRuleFinder bankTransactionRuleFinder,
IMapper mapper,
Export export)
{
this.bus = bus;
this.transactionReader = transactionReader;
this.columnFinder = columnFinder;
this.bankTransactionRuleFinder = bankTransactionRuleFinder;
this.mapper = mapper;
this.export = export;
}
