org.apache.cassandra.cql

Class SelectExpression

java.lang.Object

org.apache.cassandra.cql.SelectExpression

public class SelectExpression
extends java.lang.Object

Select expressions are analogous to the projection in a SQL query. They determine which columns will appear in the result set. SelectExpression instances encapsulate a parsed expression from a SELECT statement. See: doc/cql/CQL.html#SpecifyingColumns

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAX_COLUMNS_DEFAULT

Constructor Summary

Constructors

Constructor and Description
SelectExpression(Term first, int count, boolean reverse, boolean firstSet) Create a new SelectExpression for a list of columns.
SelectExpression(Term start, Term finish, int count, boolean reverse, boolean wildcard, boolean firstSet) Create a new SelectExpression for a range (slice) of columns.

Method Summary

Modifier and Type	Method and Description
void	and(Term addTerm) Add an additional column name to a SelectExpression.
java.util.List<Term>	getColumns()
int	getColumnsLimit()
Term	getFinish()
Term	getStart()
boolean	hasFirstSet()
boolean	isColumnList()
boolean	isColumnRange()
boolean	isColumnsReversed()
boolean	isWildcard()
void	setColumnsLimit(int limit)
void	setColumnsReversed(boolean reversed)
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

MAX_COLUMNS_DEFAULT

public static final int MAX_COLUMNS_DEFAULT

See Also:

Constant Field Values

Constructor Detail

SelectExpression

public SelectExpression(Term start,
                        Term finish,
                        int count,
                        boolean reverse,
                        boolean wildcard,
                        boolean firstSet)

Create a new SelectExpression for a range (slice) of columns.

Parameters:

start - the starting column name

finish - the finishing column name

count - the number of columns to limit the results to

reverse - true to reverse column order

wildcard - determines weather this statement is wildcard

firstSet - determines weather "FIRST" keyword was set

SelectExpression

public SelectExpression(Term first,
                        int count,
                        boolean reverse,
                        boolean firstSet)

Create a new SelectExpression for a list of columns.

Parameters:

first - the first (possibly only) column name to select on.

count - the number of columns to limit the results on

reverse - true to reverse column order

firstSet - determines weather "FIRST" keyword was set

Method Detail

and

public void and(Term addTerm)

Add an additional column name to a SelectExpression.

Parameters:

addTerm -

isColumnRange

public boolean isColumnRange()

isColumnList

public boolean isColumnList()

getColumnsLimit

public int getColumnsLimit()

isColumnsReversed

public boolean isColumnsReversed()

setColumnsReversed

public void setColumnsReversed(boolean reversed)

setColumnsLimit

public void setColumnsLimit(int limit)

hasFirstSet

public boolean hasFirstSet()

Returns:

weather expression includes "FIRST" keyword

getStart

public Term getStart()

getFinish

public Term getFinish()

getColumns

public java.util.List<Term> getColumns()

isWildcard

public boolean isWildcard()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object