Package org.apache.calcite.test.catalog

Class VirtualColumnsExpressionFactory

java.lang.Object

org.apache.calcite.sql2rel.NullInitializerExpressionFactory

org.apache.calcite.test.catalog.VirtualColumnsExpressionFactory

All Implemented Interfaces:

InitializerExpressionFactory

public class VirtualColumnsExpressionFactory
extends NullInitializerExpressionFactory

Define column strategies for the "VIRTUALCOLUMNS" table.

Field Summary

Fields inherited from class org.apache.calcite.sql2rel.NullInitializerExpressionFactory

INSTANCE

Constructor Summary

Constructors

Constructor	Description
VirtualColumnsExpressionFactory()

Method Summary

Modifier and Type	Method	Description
ColumnStrategy	generationStrategy(RelOptTable table, int iColumn)	Returns how a column is populated.
RexNode	newColumnDefaultValue(RelOptTable table, int iColumn, InitializerContext context)	Creates an expression which evaluates to the default value for a particular column.

Methods inherited from class org.apache.calcite.sql2rel.NullInitializerExpressionFactory

isGeneratedAlways, newAttributeInitializer, postExpressionConversionHook

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

VirtualColumnsExpressionFactory

public VirtualColumnsExpressionFactory()

Method Details

generationStrategy

public ColumnStrategy generationStrategy(RelOptTable table,
 int iColumn)

Description copied from interface: InitializerExpressionFactory

Returns how a column is populated.

Specified by:

generationStrategy in interface InitializerExpressionFactory

Overrides:

generationStrategy in class NullInitializerExpressionFactory

Parameters:

table - the table containing the column

iColumn - the 0-based offset of the column in the table

Returns:

generation strategy, never null

See Also:

• RelOptTable.getColumnStrategies()

newColumnDefaultValue

public RexNode newColumnDefaultValue(RelOptTable table,
 int iColumn,
 InitializerContext context)

Description copied from interface: InitializerExpressionFactory

Creates an expression which evaluates to the default value for a particular column.

If the default value comes from a un-validated SqlNode, make sure to invoke InitializerContext.validateExpression(org.apache.calcite.rel.type.RelDataType, org.apache.calcite.sql.SqlNode) first before you actually do the conversion with method InitializerContext.convertExpression(org.apache.calcite.sql.SqlNode).

Specified by:

newColumnDefaultValue in interface InitializerExpressionFactory

Overrides:

newColumnDefaultValue in class NullInitializerExpressionFactory

Parameters:

table - the table containing the column

iColumn - the 0-based offset of the column in the table

context - Context for creating the expression

Returns:

default value expression