com.metamatrix.query.sql.lang
Class Command

java.lang.Object
  com.metamatrix.query.sql.lang.Command

All Implemented Interfaces:

LanguageObject, java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

BatchedUpdateCommand, Create, CreateUpdateProcedureCommand, Drop, DynamicCommand, ProcedureContainer, QueryCommand, XQuery

public abstract class Command
extends java.lang.Object
implements LanguageObject

A Command is an interface for all the language objects that are at the root of a language object tree representing a SQL statement. For instance, a Query command represents a SQL select query, an Update command represents a SQL update statement, etc.

See Also:

Serialized Form

Field Summary

protected java.util.Map	tempGroupIDs All temporary group IDs discovered while resolving this command.
static int	TYPE_BATCHED_UPDATE Represents a batched sequence of UPDATE statements
static int	TYPE_CREATE
static int	TYPE_DELETE Represents a SQL DELETE statement
static int	TYPE_DROP
static int	TYPE_DYNAMIC
static int	TYPE_INSERT Represents a SQL INSERT statement
static int	TYPE_QUERY Represents a SQL SELECT statement
static int	TYPE_SQL Represents any SQL statement, wrapped as a string
static int	TYPE_STORED_PROCEDURE Represents a stored procedure command
static int	TYPE_UNKNOWN Represents an unknown type of command
static int	TYPE_UPDATE Represents a SQL UPDATE statement
static int	TYPE_UPDATE_PROCEDURE Represents a update stored procedure command
static int	TYPE_XQUERY Represents an XQuery

Constructor Summary

Command()

Method Summary

void	addExternalGroupsToContext(java.util.Collection groups)
void	addExternalGroupToContext(GroupSymbol group)
abstract boolean	areResultsCachable() Whether the results are cachable.
abstract java.lang.Object	clone() Implement clone to make objects cloneable.
protected void	copyMetadataState(Command copy)
java.util.List	getAllExternalGroups()
GroupContext	getExternalGroupContexts()
Option	getOption() Get the option clause for the query.
abstract java.util.List<SingleElementSymbol>	getProjectedSymbols() Get the ordered list of all elements returned by this query.
java.util.List	getSubCommands() Gets the subCommands (both embedded and non-embedded) under this command.
static int	getSubCommandsUpdatingModelCount(LanguageObject object, QueryMetadataInterface metadata)
protected int	getSubCommandsUpdatingModelCount(QueryMetadataInterface metadata)
java.util.Map	getTemporaryMetadata()
abstract int	getType() Return type of command to make it easier to build switch statements by command type.
static java.util.List	getUpdateCommandSymbol()
static java.util.List	getUpdatesCommandSymbol()
java.util.Map	getVariableValues()
GroupSymbol	getVirtualGroup()
boolean	isResolved() Indicates whether this command has been resolved or not - attempting to resolve a command that has already been resolved has undefined results.
java.lang.String	printCommandTree() Print the full tree of commands with indentation - useful for debugging
protected void	printCommandTree(java.lang.StringBuffer str, int tabLevel) Helper method to print command tree at given tab level
void	pushNewResolvingContext(java.util.Collection groups)
void	setExternalGroupContexts(GroupContext root)
void	setIsResolved(boolean isResolved) This command is intended to only be used by the QueryResolver.
void	setOption(Option option) Set the option clause for the query.
void	setTemporaryMetadata(java.util.Map metadata)
void	setVariableValues(java.util.Map parameters)
void	setVirtualGroup(GroupSymbol virtualGroup)
java.lang.String	toString() Returns a string representation of an instance of this class.
abstract int	updatingModelCount(QueryMetadataInterface metadata) Return the number of updates on physical sources by this command.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.metamatrix.query.sql.LanguageObject

acceptVisitor

Field Detail

TYPE_UNKNOWN

public static final int TYPE_UNKNOWN

Represents an unknown type of command

See Also:

Constant Field Values

TYPE_QUERY

public static final int TYPE_QUERY

Represents a SQL SELECT statement

See Also:

Constant Field Values

TYPE_INSERT

public static final int TYPE_INSERT

Represents a SQL INSERT statement

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Constant Field Values

TYPE_UPDATE

public static final int TYPE_UPDATE

Represents a SQL UPDATE statement

See Also:

Constant Field Values

TYPE_DELETE

public static final int TYPE_DELETE

Represents a SQL DELETE statement

See Also:

Constant Field Values

TYPE_SQL

public static final int TYPE_SQL

Represents any SQL statement, wrapped as a string

See Also:

Constant Field Values

TYPE_STORED_PROCEDURE

public static final int TYPE_STORED_PROCEDURE

Represents a stored procedure command

See Also:

Constant Field Values

TYPE_UPDATE_PROCEDURE

public static final int TYPE_UPDATE_PROCEDURE

Represents a update stored procedure command

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Constant Field Values

TYPE_XQUERY

public static final int TYPE_XQUERY

Represents an XQuery

See Also:

Constant Field Values

TYPE_BATCHED_UPDATE

public static final int TYPE_BATCHED_UPDATE

Represents a batched sequence of UPDATE statements

See Also:

Constant Field Values

TYPE_DYNAMIC

public static final int TYPE_DYNAMIC

See Also:

Constant Field Values

TYPE_CREATE

public static final int TYPE_CREATE

See Also:

Constant Field Values

TYPE_DROP

public static final int TYPE_DROP

See Also:

Constant Field Values

tempGroupIDs

protected java.util.Map tempGroupIDs

All temporary group IDs discovered while resolving this command. The key is a TempMetadataID and the value is an ordered List of TempMetadataID representing the elements.

Constructor Detail

Command

public Command()

Method Detail

getType

public abstract int getType()

Return type of command to make it easier to build switch statements by command type.

Returns:

Type from TYPE constants

getSubCommands

public java.util.List getSubCommands()

Gets the subCommands (both embedded and non-embedded) under this command. In general the returned list is not safe to manipulate (see @link#CommandContainer insead)

Returns:

setTemporaryMetadata

public void setTemporaryMetadata(java.util.Map metadata)

getTemporaryMetadata

public java.util.Map getTemporaryMetadata()

addExternalGroupToContext

public void addExternalGroupToContext(GroupSymbol group)

addExternalGroupsToContext

public void addExternalGroupsToContext(java.util.Collection groups)

setExternalGroupContexts

public void setExternalGroupContexts(GroupContext root)

pushNewResolvingContext

public void pushNewResolvingContext(java.util.Collection groups)

getExternalGroupContexts

public GroupContext getExternalGroupContexts()

getAllExternalGroups

public java.util.List getAllExternalGroups()

isResolved

public boolean isResolved()

Indicates whether this command has been resolved or not - attempting to resolve a command that has already been resolved has undefined results. Also, caution should be taken in modifying a command which has already been resolved, as it could result in adding unresolved components to a supposedly resolved command.

Returns:

whether this command is resolved or not.

setIsResolved

public void setIsResolved(boolean isResolved)

This command is intended to only be used by the QueryResolver.

Parameters:

isResolved - whether this command is resolved or not

clone

public abstract java.lang.Object clone()

Description copied from interface: LanguageObject

Implement clone to make objects cloneable.

Specified by:

clone in interface LanguageObject

Overrides:

clone in class java.lang.Object

Returns:

Deep clone of this object

copyMetadataState

protected void copyMetadataState(Command copy)

printCommandTree

public java.lang.String printCommandTree()

Print the full tree of commands with indentation - useful for debugging

Returns:

String String representation of command tree

printCommandTree

protected void printCommandTree(java.lang.StringBuffer str,
                                int tabLevel)

Helper method to print command tree at given tab level

Parameters:

str - String buffer to add command sub tree to

tabLevel - Number of tabs to print this command at

getOption

public Option getOption()

Get the option clause for the query.

Returns:

option clause

setOption

public void setOption(Option option)

Set the option clause for the query.

Parameters:

option - New option clause

getProjectedSymbols

public abstract java.util.List<SingleElementSymbol> getProjectedSymbols()

Get the ordered list of all elements returned by this query. These elements may be ElementSymbols or ExpressionSymbols but in all cases each represents a single column.

Returns:

Ordered list of SingleElementSymbol

areResultsCachable

public abstract boolean areResultsCachable()

Whether the results are cachable.

Returns:

True if the results are cachable; false otherwise.

getUpdateCommandSymbol

public static java.util.List getUpdateCommandSymbol()

getUpdatesCommandSymbol

public static java.util.List getUpdatesCommandSymbol()

updatingModelCount

public abstract int updatingModelCount(QueryMetadataInterface metadata)
                                throws MetaMatrixComponentException

Return the number of updates on physical sources by this command.

Parameters:

metadata - QueryMetadataInterface

Returns:

The number of updates on physical sources by this command.

Throws:

MetaMatrixComponentException

Since:

4.3

getSubCommandsUpdatingModelCount

protected int getSubCommandsUpdatingModelCount(QueryMetadataInterface metadata)
                                        throws MetaMatrixComponentException

Throws:

MetaMatrixComponentException

getSubCommandsUpdatingModelCount

public static int getSubCommandsUpdatingModelCount(LanguageObject object,
                                                   QueryMetadataInterface metadata)
                                            throws MetaMatrixComponentException

Throws:

MetaMatrixComponentException

getVirtualGroup

public GroupSymbol getVirtualGroup()

setVirtualGroup

public void setVirtualGroup(GroupSymbol virtualGroup)

getVariableValues

public java.util.Map getVariableValues()

setVariableValues

public void setVariableValues(java.util.Map parameters)

toString

public java.lang.String toString()

Returns a string representation of an instance of this class.

Overrides:

toString in class java.lang.Object

Returns:

String representation of object