T IQueryExecutor.ExecuteScalar <T>(QueryModel queryModel)
{
var mapping = _schema.MappingFor(queryModel.SelectClause.Selector.Type);
var documentQuery = new DocumentQuery(mapping, queryModel, _serializer);
_schema.EnsureStorageExists(mapping.DocumentType);
if (queryModel.ResultOperators.OfType <AnyResultOperator>().Any())
{
var anyCommand = new NpgsqlCommand();
documentQuery.ConfigureForAny(anyCommand);
return(_runner.Execute(anyCommand, c => (T)c.ExecuteScalar()));
}
if (queryModel.ResultOperators.OfType <CountResultOperator>().Any())
{
var countCommand = new NpgsqlCommand();
documentQuery.ConfigureForCount(countCommand);
return(_runner.Execute(countCommand, c =>
{
var returnValue = c.ExecuteScalar();
return Convert.ToInt32(returnValue).As <T>();
}));
}
throw new NotSupportedException();
}
private Task <T> ExecuteScalar <T>(ResultOperatorBase scalarResultOperator, QueryModel queryModel, CancellationToken token)
{
var mapping = _schema.MappingFor(queryModel.SelectClause.Selector.Type);
var documentQuery = new DocumentQuery(mapping, queryModel, _serializer);
_schema.EnsureStorageExists(mapping.DocumentType);
if (scalarResultOperator is AnyResultOperator)
{
var anyCommand = new NpgsqlCommand();
documentQuery.ConfigureForAny(anyCommand);
return(_runner.ExecuteAsync(anyCommand, async(c, tkn) =>
{
var result = await c.ExecuteScalarAsync(tkn).ConfigureAwait(false);
return (T)result;
}, token));
}
if (scalarResultOperator is CountResultOperator)
{
var countCommand = new NpgsqlCommand();
documentQuery.ConfigureForCount(countCommand);
return(_runner.ExecuteAsync(countCommand, async(c, tkn) =>
{
var returnValue = await c.ExecuteScalarAsync(tkn).ConfigureAwait(false);
return Convert.ToInt32(returnValue).As <T>();
}, token));
}
if (scalarResultOperator is LongCountResultOperator)
{
var countCommand = new NpgsqlCommand();
documentQuery.ConfigureForCount(countCommand);
return(_runner.ExecuteAsync(countCommand, async(c, tkn) =>
{
var returnValue = await c.ExecuteScalarAsync(tkn).ConfigureAwait(false);
return Convert.ToInt64(returnValue).As <T>();
}, token));
}
throw new NotSupportedException();
}
