org.apache.cassandra.cql
Class SelectExpression

java.lang.Object
  extended by 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
static int MAX_COLUMNS_DEFAULT
           
 
Constructor Summary
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
 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


Copyright © 2012 The Apache Software Foundation