Package org.apache.calcite.schema

Interface ExtensibleTable

All Superinterfaces:

Table

public interface ExtensibleTable
extends Table

Table whose row type can be extended to include extra fields.

In some storage systems, especially those with "late schema", there may exist columns that have values in the table but which are not declared in the table schema. However, a particular query may wish to reference these columns as if they were defined in the schema. Calling the extend(java.util.List<org.apache.calcite.rel.type.RelDataTypeField>) method creates a temporarily extended table schema.

If the table implements extended interfaces such as ScannableTable, FilterableTable or ProjectableFilterableTable, you may wish to make the table returned from extend(java.util.List<org.apache.calcite.rel.type.RelDataTypeField>) implement these interfaces as well.

Method Summary

Modifier and Type	Method	Description
Table	extend(List<RelDataTypeField> fields)	Returns a table that has the row type of this table plus the given fields.
int	getExtendedColumnOffset()	Returns the starting offset of the first extended column, which may differ from the field count when the table stores metadata columns that are not counted in the row-type field count.

Methods inherited from interface org.apache.calcite.schema.Table

getJdbcTableType, getRowType, getStatistic, isRolledUp, rolledUpColumnValidInsideAgg

Method Details

extend

Table extend(List<RelDataTypeField> fields)

Returns a table that has the row type of this table plus the given fields.

getExtendedColumnOffset

int getExtendedColumnOffset()

Returns the starting offset of the first extended column, which may differ from the field count when the table stores metadata columns that are not counted in the row-type field count.