org.edg.info.sqlutil.parsql
Class SelectItem

java.lang.Object
  extended byorg.edg.info.sqlutil.parsql.AliasedName
      extended byorg.edg.info.sqlutil.parsql.SelectItem
All Implemented Interfaces:
java.io.Serializable

public class SelectItem
extends AliasedName

SelectItem: an item in the SELECT part of an SQL query. (The SELECT part of a query is a Vector of SelectItem).

See Also:
Serialized Form

Field Summary
 
Fields inherited from class org.edg.info.sqlutil.parsql.AliasedName
FORM_COLUMN, FORM_TABLE
 
Constructor Summary
SelectItem()
          Create a new SELECT item
SelectItem(java.lang.String fullname)
          Create a new SELECT item, given its name (for column names and wildcards).
 
Method Summary
 java.lang.String getAggregate()
          If this item is an aggregate function, return the function name.
 ExpSelConst getExpression()
          DOCUMENT ME!
 boolean isCountDistinct()
           
 boolean isExpression()
          DOCUMENT ME!
 void setAggregate(java.lang.String a)
          Initialize an aggregate function on this item (generally SUM, AVG, MAX, MIN) Example: SELECT AVG(age) FROM people; -> The aggregate function is AVG.
 void setExpression(ExpSelConst e)
          Initialize this SELECT item as an SQL expression (not a column name nor wildcard) Example: SELECT a+b FROM table1; (a+b is an expression)
 java.lang.String toString()
          DOCUMENT ME!
 
Methods inherited from class org.edg.info.sqlutil.parsql.AliasedName
getAlias, getColumn, getSchema, getTable, isWildcard, setAlias
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

SelectItem

public SelectItem()
Create a new SELECT item


SelectItem

public SelectItem(java.lang.String fullname)
Create a new SELECT item, given its name (for column names and wildcards).

Parameters:
fullname - A string that represents a column name or wildcard (example: a.).
Method Detail

setAggregate

public void setAggregate(java.lang.String a)
Initialize an aggregate function on this item (generally SUM, AVG, MAX, MIN) Example: SELECT AVG(age) FROM people; -> The aggregate function is AVG.

Parameters:
a - The name of the aggregate function (a String, like SUM, AVG, MAX, MIN)

getAggregate

public java.lang.String getAggregate()
If this item is an aggregate function, return the function name.

Returns:
The name of an aggregate function (generally SUM, AVG, MAX, MIN), or null if there's no aggregate. Example: SELECT name, AVG(age) FROM people; -> null for the "name" item, and "AVG" for the "AVG(age)" item.

isCountDistinct

public boolean isCountDistinct()

setExpression

public void setExpression(ExpSelConst e)
Initialize this SELECT item as an SQL expression (not a column name nor wildcard) Example: SELECT a+b FROM table1; (a+b is an expression)

Parameters:
e - DOCUMENT ME!

getExpression

public ExpSelConst getExpression()
DOCUMENT ME!

Returns:
An SQL Expression if this SELECT item is an expression, a Constant if it is a column name, null if it is a wildcard

isExpression

public boolean isExpression()
DOCUMENT ME!

Returns:
true if this item is an SQL expression, false if not. (Example: SELECT a+b, c FROM num; -> a+b is an expression, not c)

toString

public java.lang.String toString()
DOCUMENT ME!

Overrides:
toString in class AliasedName
Returns:
DOCUMENT ME!