com.google.visualization.datasource.query
Class QuerySelection

java.lang.Object
  extended by com.google.visualization.datasource.query.QuerySelection

public class QuerySelection
extends Object

Selection definition for a query. Selection is defined as a list of column IDs. It can also include aggregations for grouping/pivoting and scalar functions.

Author:
Itai R.

Constructor Summary
QuerySelection()
          Construct an empty selection list.
QuerySelection(QuerySelection source)
          Copy constructor.
 
Method Summary
 void addColumn(AbstractColumn column)
          Adds a column to the column list.
 boolean equals(Object obj)
           
 List<AggregationColumn> getAggregationColumns()
          Returns all the columns that are AggregationColumns including aggregation columns that are inside scalar function columns (e.g., year(min(a1))).
 List<AbstractColumn> getColumns()
          Returns the list of columns.
 List<ScalarFunctionColumn> getScalarFunctionColumns()
          Returns all the columns that are ScalarFunctionColumns including scalar functions columns that are inside other scalar function columns (e.g., sum(year(a), year(b))).
 List<SimpleColumn> getSimpleColumns()
          Returns all the columns that are SimpleColumns including those inside scalar function columns (e.g, year(a1)).
 int hashCode()
           
 boolean isEmpty()
          Returns true if the selection list is empty.
 String toQueryString()
          Returns a string that when fed to the query parser would produce an equal QuerySelection.
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

QuerySelection

public QuerySelection()
Construct an empty selection list.


QuerySelection

public QuerySelection(QuerySelection source)
Copy constructor.

Parameters:
source - The source query selection from which to construct.
Method Detail

isEmpty

public boolean isEmpty()
Returns true if the selection list is empty.

Returns:
True if the selection list is empty.

addColumn

public void addColumn(AbstractColumn column)
Adds a column to the column list.

Parameters:
column - The column to select.

getColumns

public List<AbstractColumn> getColumns()
Returns the list of columns. This list is immutable.

Returns:
The list of columns. This list is immutable.

getAggregationColumns

public List<AggregationColumn> getAggregationColumns()
Returns all the columns that are AggregationColumns including aggregation columns that are inside scalar function columns (e.g., year(min(a1))).

Returns:
All the columns that are AggregationColumns.

getSimpleColumns

public List<SimpleColumn> getSimpleColumns()
Returns all the columns that are SimpleColumns including those inside scalar function columns (e.g, year(a1)). Does not return simple columns inside aggregation columns (e.g., sum(a1)).

Returns:
All the columns that are SimpleColumns.

getScalarFunctionColumns

public List<ScalarFunctionColumn> getScalarFunctionColumns()
Returns all the columns that are ScalarFunctionColumns including scalar functions columns that are inside other scalar function columns (e.g., sum(year(a), year(b))).

Returns:
all the columns that are ScalarFunctionColumns.

hashCode

public int hashCode()
Overrides:
hashCode in class Object

equals

public boolean equals(Object obj)
Overrides:
equals in class Object

toQueryString

public String toQueryString()
Returns a string that when fed to the query parser would produce an equal QuerySelection. The string is returned without the SELECT keyword.

Returns:
The query string.


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