private async Task<string> GetFormattedResultAsync(ResultSetPrinter printer)
{
var task = new Task<string>(printer.GetFormattedResults);
task.Start();
return await task;
}
private async void CountQuery(string city)
{
var query =
new ResultSetPrinter(
new RecordParser(
new CountRecordProvider("city", "id",
new PracticeDatabaseReader("practices.dat", indexManager,
new List<IWhereQueryConstraint>
{
new EqualityConstraint("city", "LONDON", byteConverter)
}))));
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
var results = await GetFormattedResultAsync(query);
stopwatch.Stop();
Output += $"{results}Time: {stopwatch.ElapsedMilliseconds} ms\n";
}
private async void PostcodeQuery()
{
var query =
new ResultSetPrinter(
new RecordParser(
new LimitRecordProvider(5,
new SortingRecordProvider("cost",
new SumRecordProvider("postal_code", "cost",
new SelectionRecordProvider(new[] {"cost", "postal_code"},
new JoinRecordProvider(
new SelectionRecordProvider(new List<string> {"cost", "practice"},
new OrderDatabaseReader("orders.dat", indexManager, QueryMode.Auto,
new List<IWhereQueryConstraint>())),
new SelectionRecordProvider(new List<string> {"id", "postal_code"},
new PracticeDatabaseReader("practices.dat", indexManager,
new List<IWhereQueryConstraint>())),
"practice",
"id"))),
SortingRecordProvider.Order.DESCENDING
))));
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
var results = await GetFormattedResultAsync(query);
stopwatch.Stop();
Output += $"{results}Time: {stopwatch.ElapsedMilliseconds} ms\n";
}
private async void AverageQuery(string product)
{
var query =
new ResultSetPrinter(
new RecordParser(
new WhereRecordProvider(
new AverageRecordProvider("bnf_name", "cost",
new OrderDatabaseReader("orders.dat", indexManager, QueryMode.Auto,
new List<IWhereQueryConstraint>())),
new[] {new EqualityConstraint("bnf_name", "Peppermint Oil", byteConverter)})));
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
var results = await GetFormattedResultAsync(query);
stopwatch.Stop();
Output += $"{results}Time: {stopwatch.ElapsedMilliseconds} ms\n";
}
private async void RegionQuery()
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
var averageQuery = new RecordParser(
new UngroupedAverageProvider("cost",
new SelectionRecordProvider(new[] {"cost", "bnf_name"},
new OrderDatabaseReader("orders.dat", indexManager, QueryMode.Auto,
new List<IWhereQueryConstraint>
{
new ContainsQueryConstraint("bnf_name", "Flucloxacillin"),
new Not(new ContainsQueryConstraint("bnf_name", "Co-Fluampicil")),
new Not(new EqualityConstraint("bnf_name", "", byteConverter))
}))));
float avg = (float) (await GetUnformattedResultAsync(averageQuery)).First()["avg_of_cost"];
Func<RecordMetaData, byte[], dynamic> differ = (recordMetaData, row) =>
{
float value = BitConverter.ToSingle(row, recordMetaData.ColumnDescriptors["avg_of_cost"].Offset);
return value - avg;
};
var query =
new ResultSetPrinter(
new RecordParser(
new ComputedFieldProvider("diff", ColumnType.Float, differ,
new AverageRecordProvider("region", "cost",
new WhereRecordProvider(
new JoinRecordProvider(
new SelectionRecordProvider(new List<string> {"cost", "practice", "bnf_name"},
new OrderDatabaseReader("orders.dat", indexManager, QueryMode.Auto,
new List<IWhereQueryConstraint>())),
new SelectionRecordProvider(new List<string> {"id", "region"},
new PracticeDatabaseReader("practices.dat", indexManager,
new List<IWhereQueryConstraint>())),
"practice",
"id"),
new List<IWhereQueryConstraint>
{
new ContainsQueryConstraint("bnf_name", "Flucloxacillin"),
new Not(new ContainsQueryConstraint("bnf_name", "Co-Fluampicil")),
new Not(new EqualityConstraint("bnf_name", "", byteConverter))
})))));
var results = await GetFormattedResultAsync(query);
stopwatch.Stop();
Output += $"{results}Time: {stopwatch.ElapsedMilliseconds} ms\n";
}