org.h2.command.dml

Class SelectListColumnResolver

java.lang.Object

org.h2.command.dml.SelectListColumnResolver

All Implemented Interfaces:

ColumnResolver

public class SelectListColumnResolver
extends java.lang.Object
implements ColumnResolver

This class represents a column resolver for the column list of a SELECT statement. It is used to resolve select column aliases in the HAVING clause. Example:

SELECT X/3 AS A, COUNT(*) FROM SYSTEM_RANGE(1, 10) GROUP BY A HAVING A>2;

Method Summary

Modifier and Type	Method and Description
Column[]	getColumns() Get the column list.
java.lang.String	getDerivedColumnName(Column column) Get derived column name, or null.
Column	getRowIdColumn() Get the row id pseudo column, if there is one.
java.lang.String	getSchemaName() Get the schema name.
Select	getSelect() Get the select statement.
Column[]	getSystemColumns() Get the list of system columns, if any.
java.lang.String	getTableAlias() Get the table alias.
TableFilter	getTableFilter() Get the table filter.
Value	getValue(Column column) Get the value for the given column.
Expression	optimize(ExpressionColumn expressionColumn, Column column) Get the expression that represents this column.

Methods inherited from class java.lang.Object

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

Method Detail

getColumns

public Column[] getColumns()

Description copied from interface: ColumnResolver

Get the column list.

Specified by:

getColumns in interface ColumnResolver

Returns:

the column list

getDerivedColumnName

public java.lang.String getDerivedColumnName(Column column)

Description copied from interface: ColumnResolver

Get derived column name, or null.

Specified by:

getDerivedColumnName in interface ColumnResolver

Parameters:

column - column

Returns:

derived column name, or null

getSchemaName

public java.lang.String getSchemaName()

Description copied from interface: ColumnResolver

Get the schema name.

Specified by:

getSchemaName in interface ColumnResolver

Returns:

the schema name

getSelect

public Select getSelect()

Description copied from interface: ColumnResolver

Get the select statement.

Specified by:

getSelect in interface ColumnResolver

Returns:

the select statement

getSystemColumns

public Column[] getSystemColumns()

Description copied from interface: ColumnResolver

Get the list of system columns, if any.

Specified by:

getSystemColumns in interface ColumnResolver

Returns:

the system columns or null

getRowIdColumn

public Column getRowIdColumn()

Description copied from interface: ColumnResolver

Get the row id pseudo column, if there is one.

Specified by:

getRowIdColumn in interface ColumnResolver

Returns:

the row id column or null

getTableAlias

public java.lang.String getTableAlias()

Description copied from interface: ColumnResolver

Get the table alias.

Specified by:

getTableAlias in interface ColumnResolver

Returns:

the table alias

getTableFilter

public TableFilter getTableFilter()

Description copied from interface: ColumnResolver

Get the table filter.

Specified by:

getTableFilter in interface ColumnResolver

Returns:

the table filter

getValue

public Value getValue(Column column)

Description copied from interface: ColumnResolver

Get the value for the given column.

Specified by:

getValue in interface ColumnResolver

Parameters:

column - the column

Returns:

the value

optimize

public Expression optimize(ExpressionColumn expressionColumn,
                           Column column)

Description copied from interface: ColumnResolver

Get the expression that represents this column.

Specified by:

optimize in interface ColumnResolver

Parameters:

expressionColumn - the expression column

column - the column

Returns:

the optimized expression