dk.eobjects.metamodel.query
Class Query

java.lang.Object
  dk.eobjects.metamodel.query.Query

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

public class Query
extends java.lang.Object
implements java.lang.Cloneable, java.io.Serializable

Represents a query to retrieve data by. A query is made up of six clauses, equivalent to the SQL standard:

• the SELECT clause, which define the wanted columns of the resulting DataSet
• the FROM clause, which define where to retrieve the data from
• the WHERE clause, which define filters on the retrieved data
• the GROUP BY clause, which define if the result should be grouped and aggregated according to some columns acting as categories
• the HAVING clause, which define filters on the grouped data
• the ORDER BY clause, which define sorting of the resulting dataset

Queries are executed using the DataContext.executeQuery method or can alternatively be used directly in JDBC by using the toString() method.

See Also:

DataContext, Serialized Form

Constructor Summary

Query()

Method Summary

Query	clone()
boolean	equals(java.lang.Object obj)
Query	from(FromItem... items)
Query	from(java.lang.String expression)
Query	from(Table table)
Query	from(Table table, java.lang.String alias)
FromClause	getFromClause()
GroupByClause	getGroupByClause()
FilterClause	getHavingClause()
java.lang.Integer	getMaxRows()
OrderByClause	getOrderByClause()
SelectClause	getSelectClause()
FilterClause	getWhereClause()
Query	groupBy(Column... columns)
Query	groupBy(GroupByItem... items)
Query	having(Column column, OperatorType operatorType, java.lang.Object operand)
Query	having(FilterItem... items)
Query	having(java.lang.String expression)
Query	orderBy(Column column)
Query	orderBy(Column column, boolean ascending) Deprecated. use orderBy(Column, Direction) instead
Query	orderBy(Column column, OrderByItem.Direction direction)
Query	orderBy(OrderByItem... items)
Query	select(Column... columns)
Query	select(SelectItem... items)
Query	select(java.lang.String expression)
Query	select(java.lang.String expression, java.lang.String alias)
Query	selectCount()
Query	selectDistinct()
Query	setMaxRows(java.lang.Integer maxRows) Sets the maximum number of rows to be queried.
java.lang.String	toString()
Query	where(Column column, OperatorType operatorType, java.lang.Object operand)
Query	where(FilterItem... items)
Query	where(java.lang.String expression)

Methods inherited from class java.lang.Object

finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Query

public Query()

Method Detail

select

public Query select(Column... columns)

select

public Query select(SelectItem... items)

select

public Query select(java.lang.String expression,
                    java.lang.String alias)

select

public Query select(java.lang.String expression)

selectDistinct

public Query selectDistinct()

selectCount

public Query selectCount()

from

public Query from(FromItem... items)

from

public Query from(Table table)

from

public Query from(java.lang.String expression)

from

public Query from(Table table,
                  java.lang.String alias)

groupBy

public Query groupBy(GroupByItem... items)

groupBy

public Query groupBy(Column... columns)

orderBy

public Query orderBy(OrderByItem... items)

orderBy

public Query orderBy(Column column)

orderBy

@Deprecated
public Query orderBy(Column column,
                                boolean ascending)

Deprecated. use orderBy(Column, Direction) instead

orderBy

public Query orderBy(Column column,
                     OrderByItem.Direction direction)

where

public Query where(FilterItem... items)

where

public Query where(java.lang.String expression)

where

public Query where(Column column,
                   OperatorType operatorType,
                   java.lang.Object operand)

having

public Query having(FilterItem... items)

having

public Query having(Column column,
                    OperatorType operatorType,
                    java.lang.Object operand)

having

public Query having(java.lang.String expression)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getSelectClause

public SelectClause getSelectClause()

getFromClause

public FromClause getFromClause()

getWhereClause

public FilterClause getWhereClause()

getGroupByClause

public GroupByClause getGroupByClause()

getHavingClause

public FilterClause getHavingClause()

getOrderByClause

public OrderByClause getOrderByClause()

setMaxRows

public Query setMaxRows(java.lang.Integer maxRows)

Sets the maximum number of rows to be queried. If the result of the query yields more rows they should be discarded.

Parameters:

maxRows - the number of desired maximum rows. Can be null (default) for no limits

getMaxRows

public java.lang.Integer getMaxRows()

Returns:

the number of maximum rows to yield from executing this query or null if no maximum/limit is set.

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

clone

public Query clone()

Overrides:

clone in class java.lang.Object