public Task <IPhysicalOperator <RowHolder> > BuildStatement(Sql.sqlStatement statement, ITransaction tran, IPhysicalOperator <RowHolder> source, InputStringNormalizer inputStringNormalizer)
{
Sql.columnSelect[] columns = new Sql.columnSelect[0];
Tuple <Sql.aggType, string>[] aggregates = new Tuple <Sql.aggType, string> [0];
if (!statement.Columns.IsStar)
{
columns = (((Sql.selectType.ColumnList)statement.Columns).Item).ToArray();
aggregates = columns
.Where(c => c.IsAggregate == true)
.Select(c => ((Sql.columnSelect.Aggregate)c).Item).ToArray();
}
if (statement.GroupBy.Any() || aggregates.Any())
{
string[] groupByColumns = statement.GroupBy.ToArray();
GroupByFunctors groupByFunctors = GroupByStatementBuilder.EvalGroupBy(groupByColumns, columns, source.GetOutputColumns());
IPhysicalOperator <RowHolder> phyOpGroupBy = new PhyOpGroupBy(source, groupByFunctors);
return(Task.FromResult(phyOpGroupBy));
}
else
{
return(Task.FromResult(source));
}
}
public async Task <IPhysicalOperator <RowHolder> > BuildStatement(Sql.sqlStatement statement, ITransaction tran, IPhysicalOperator <RowHolder> source, InputStringNormalizer stringNormalizer)
{
if (statement.Joins.Any())
{
IPhysicalOperator <RowHolder> currJoinSource = source;
for (int i = 0; i < statement.Joins.Length; i++)
{
if (!statement.Joins[i].Item2.IsInner)
{
throw new NotSupportedException("Only inner join is supported at this point.");
}
MetadataTable joinRightTable = await this.metadataManager.GetTableManager().GetByName(statement.Joins[i].Item1, tran).ConfigureAwait(false);
PhyOpScan scanOpRight = new PhyOpScan(joinRightTable.Collection, tran, joinRightTable.Columns, joinRightTable.TableName);
Func <RowHolder, bool> filter = (_) => true;
if (FSharpOption <Sql.where> .get_IsSome(statement.Joins[i].Item3))
{
filter = FilterStatementBuilder.EvalWhere(
statement.Joins[i].Item3.Value,
QueryProcessingAccessors.MergeColumns(currJoinSource.GetOutputColumns(), scanOpRight.GetOutputColumns()),
stringNormalizer);
}
currJoinSource = new PhyOpLoopInnerJoin(currJoinSource, scanOpRight, filter);
}
return(currJoinSource);
}
else
{
return(source);
}
}
public Task <IPhysicalOperator <RowHolder> > BuildStatement(Sql.sqlStatement statement, ITransaction tran, IPhysicalOperator <RowHolder> source, InputStringNormalizer inputStringNormalizer)
{
if (FSharpOption <Sql.where> .get_IsSome(statement.Where))
{
Sql.where whereStatement = statement.Where.Value;
IPhysicalOperator <RowHolder> filterOp = new PhyOpFilter(source, FilterStatementBuilder.EvalWhere(whereStatement, source.GetOutputColumns(), inputStringNormalizer));
return(Task.FromResult(filterOp));
}
else
{
return(Task.FromResult(source));
}
}
public Task <IPhysicalOperator <RowHolder> > BuildStatement(Sql.sqlStatement statement, ITransaction tran, IPhysicalOperator <RowHolder> source, InputStringNormalizer inputStringNormalizer)
{
if (statement.OrderBy.IsEmpty)
{
return(Task.FromResult(source));
}
OrderByColumn[] orderByColumns = GetOrderByColumns(source.GetOutputColumns(), statement.OrderBy);
IPhysicalOperator <RowHolder> phyOpOrderBy = new PhyOpOrderBy(source, new RowHolderOrderByComparer(orderByColumns));
return(Task.FromResult(phyOpOrderBy));
}
public async Task <RowProvider> ParseSqlStatement(Sql.sqlStatement sqlStatement, ITransaction tran, InputStringNormalizer stringNormalizer)
{
// TODO: query builder is currently manual. i.e. SCAN -> optional(JOINS) -> optional(FILTER) -> GROUP BY -> ORDER BY/PROJECT.
// In future we need to build proper algebrizer, relational algebra rules and work on QO.
IPhysicalOperator <RowHolder> source = null;
foreach (IStatementTreeBuilder builder in this.statementBuildersList)
{
source = await builder.BuildStatement(sqlStatement, tran, source, stringNormalizer);
}
return(new RowProvider(source.Iterate(tran), source.GetOutputColumns()));
}
public async Task <IPhysicalOperator <RowHolder> > BuildStatement(Sql.sqlStatement statement, ITransaction tran, IPhysicalOperator <RowHolder> source, InputStringNormalizer stringNormalizer)
{
if (source != null)
{
// For now source for scan must be null.
// with subquery expression this will change.
throw new ArgumentException();
}
string tableName = statement.Table;
MetadataTablesManager tableManager = metadataManager.GetTableManager();
MetadataTable table = await tableManager.GetByName(tableName, tran).ConfigureAwait(false);
// Since we currently don't support indexes we can only build scan operation.
return(new PhyOpScan(table.Collection, tran, table.Columns, table.TableName));
}
public Task <IPhysicalOperator <RowHolder> > BuildStatement(Sql.sqlStatement statement, ITransaction tran, IPhysicalOperator <RowHolder> source, InputStringNormalizer inputStringNormalizer)
{
Sql.columnSelect[] columns = new Sql.columnSelect[0];
bool isStar = false;
string[] projections = new string[0];
if (statement.GroupBy.Any())
{
// no job for me, this is group by.
return(Task.FromResult(source));
}
if (!statement.Columns.IsStar)
{
columns = (((Sql.selectType.ColumnList)statement.Columns).Item).ToArray();
if (columns.Any(c => c.IsAggregate == true))
{
// No job for me, this is aggregation.
return(Task.FromResult(source));
}
projections = columns
.Where(c => c.IsProjection == true)
.Select(c => ((Sql.columnSelect.Projection)c).Item).ToArray();
}
else
{
isStar = true;
}
int?topRows = null;
if (FSharpOption <int> .get_IsSome(statement.Top))
{
topRows = statement.Top.Value;
if (topRows < 1)
{
throw new InvalidTopCountException();
}
}
if (isStar)
{
// no need for project, just return everything.
IPhysicalOperator <RowHolder> projectOp = new PhyOpProject(source, topRows);
return(Task.FromResult(projectOp));
}
else
{
// Project Op.
List <MetadataColumn> columnMapping = new List <MetadataColumn>();
foreach (string columnName in projections)
{
MetadataColumn mc = QueryProcessingAccessors.GetMetadataColumn(columnName, source.GetOutputColumns());
columnMapping.Add(mc);
}
IPhysicalOperator <RowHolder> projectOp = new PhyOpProject(source, columnMapping.Select(mc => mc.ColumnId).ToArray(), topRows);
return(Task.FromResult(projectOp));
}
}
