Apache Derby Database Engine and Embedded JDBC Driver 10.17.1.0 · org.apache.derby.impl.store.access.btree.ControlRow

Modifier and Type	Field and Description
private BTree	btree A copy of the Conglomerate that describes the owning conglom.
protected static final int	CR_COLID_FIRST Column number assignments for columns of the control row.
protected static final int	CR_COLID_LAST
protected static final FormatableBitSet	CR_CONGLOM_BITSET
protected static final int	CR_CONGLOM_COLID
protected static final FormatableBitSet	CR_ISROOT_BITSET
protected static final int	CR_ISROOT_COLID
protected static final FormatableBitSet	CR_LEFTSIB_BITSET
protected static final int	CR_LEFTSIB_COLID
protected static final FormatableBitSet	CR_LEVEL_BITSET
protected static final int	CR_LEVEL_COLID
protected static final int	CR_NCOLUMNS
protected static final FormatableBitSet	CR_PARENT_BITSET
protected static final int	CR_PARENT_COLID
protected static final FormatableBitSet	CR_RIGHTSIB_BITSET
protected static final int	CR_RIGHTSIB_COLID
protected static final int	CR_SLOT The slot at which all control rows reside.
protected static final FormatableBitSet	CR_VERSION_BITSET bit sets used to fetch single columns at a time.
protected static final int	CR_VERSION_COLID
protected FetchDescriptor	fetchDesc FetchDescriptor used to replace fetchFieldFromSlot() calls.
private SQLLongint	isRoot Is this page the root of the btree?
protected transient int	last_search_result In memory hint about where to begin the binary search to find a key on the the current control page.
private SQLLongint	leftSiblingPageNumber Pointer to page which is "left" at the current level.
private SQLLongint	level The level of the btree.
protected Page	page The page that this control row describes.
private SQLLongint	parentPageNumber The parent page of the current page.
private SQLLongint	rightSiblingPageNumber Pointer to page which is "right" at the current level.
protected DataValueDescriptor[]	row The page that this control row describes.
protected DataValueDescriptor[]	scratch_row row used to replace fetchFieldFromSlot() calls.
public static final int	SPLIT_FLAG_FIRST_IN_TABLE
public static final int	SPLIT_FLAG_FIRST_ON_PAGE
public static final int	SPLIT_FLAG_LAST_IN_TABLE
public static final int	SPLIT_FLAG_LAST_ON_PAGE Values passed in the flag argument to splitFor.
protected transient boolean	use_last_search_result_hint In memory hint about whether to use the last_search_result hint during search.
private StorableFormatId	version Version indentifier of the control row within the page.

Access	Constructor and Description
protected	ControlRow() No arg constructor.
protected	ControlRow(OpenBTree Static information about the btree. btree, Page The page described by this control row. page, int level, ControlRow The parent page of this page, "null" if this page is root or if not maintaining parent links. parent, boolean Is this page the root of the tree? isRoot) Constructor for making a new control row as part of allocating a new page.
protected	ControlRow(ContainerHandle Open container container, Page The page described by this control row. page) Constructor for making a control row for an existing page.

Method Summary

Modifier and Type	Method and Description
public void	auxObjectInvalidated() Implements org.apache.derby.iapi.store.raw.AuxObject.auxObjectInvalidated. Called when the page is being evicted from cache or when a rollback happened on the page and may possibly have changed the control row's value
protected abstract int	Returns: The identifier to be used to open the conglomerate later. checkConsistency(OpenBTree The open btree to associate latches/locks with. btree, ControlRow The parent page of this page, "null" if this page is root or if not maintaining parent links. parent, boolean Should the consistency check go to other pages (this option breaks the latch protocol). check_other_pages) Check consistency of the page and its children, returning the number of pages seen, and throwing errors if inconsistencies are found.
protected void	checkGeneric(OpenBTree btree, ControlRow parent, boolean check_other_pages) Perform consistency checks which are common to all pages that derive from ControlRow (both leaf and branch pages).</menu>
protected boolean	checkRowOrder(OpenBTree btree, ControlRow parent) Check that all rows on the page are in order.
protected void	checkSiblings(OpenBTree btree) Perform checks on the siblings of this page: make sure that they're at the same level as this page, that they're mutually linked together, and that the first/last keys on sibling pages are in order.
public static int	compareIndexRowFromPageToKey(ControlRow Controlrow of page to get target row from. indexpage, int Slot to get control row from. slot, DataValueDescriptor[] template of the target row (the row in the index). indexrow, DataValueDescriptor[] the (possibly partial) search key. key, int the number of columns to compare. nCompareCols, int what to return on a partial key match. partialKeyOrder, boolean[] column sort order information ascOrDesc) Compare two orderable rows, considering nCompareCols, and return -1, 0, or 1 depending on whether the first row (indexrow) is less than, equal to, or greater than the second (key).
public static int	compareIndexRowToKey(DataValueDescriptor[] indexrow, DataValueDescriptor[] key, int nCompareCols, int partialKeyOrder, boolean[] ascOrDesc)
protected boolean	compareRowsOnSiblings(OpenBTree btree, ControlRow left_sib, ControlRow right_sib)
protected abstract void	controlRowInit() Perform page specific initialization.
public String	Returns: string with all info. debugPage(OpenBTree open_btree) Dump complete information about control row and rows on the page.
public static ControlRow	get(OpenBTree open_btree, long pageNumber) Get the control row from the given page in the b-tree.
public static ControlRow	get(ContainerHandle container, long pageNumber)
public BTree	Returns: format id of a row on the page. getConglom(int format_id) Get format id information for row on page.
protected static ControlRow	getControlRowForPage(ContainerHandle container, Page page)
protected boolean	getIsRoot()
protected abstract ControlRow	Returns: The page which is the leftmost child of this page. getLeftChild(OpenBTree The open btree to associate latches/locks with. btree) Return the left child pointer for the page.
public ControlRow	getLeftSibling(OpenBTree btree) Get the control row for this page's left sibling, or null if there is no left sibling (which probably means it's the leftmost page at its level).
public long	getleftSiblingPageNumber() Get the page number of the left sibling.
protected int	getLevel()
public static ControlRow	getNoWait(OpenBTree open_btree, long pageNumber) Get the control row for the given page if the latch on the page can be obtained without waiting, else return null.
protected abstract int	Returns: The total number of columns in the control row. getNumberOfControlRowColumns() Get the number of columns in the control row.
public Page	getPage()
protected long	getParentPageNumber() Get the page number of the parent, if it's being maintained.
protected abstract ControlRow	Returns: The page which is the rightmost child of this page. getRightChild(OpenBTree The open btree to associate latches/locks with. btree) Return the right child pointer for the page.
protected ControlRow	getRightSibling(OpenBTree open_btree) Return the control row for this page's right sibling.
protected long	getrightSiblingPageNumber() Get the page number of the right sibling.
protected final DataValueDescriptor[]	Returns: The row. getRow() Get the row.
public DataValueDescriptor[]	Returns: Newly allocated template. getRowTemplate(OpenBTree open_btree) Return a new template for reading a data row from the current page.
protected int	Returns: version of the control row. getVersion() Get version of the control row.
public abstract boolean	Returns: true if the current page is the leftmost leaf of the tree, else return false. isLeftmostLeaf() Is the current page the leftmost leaf of tree?
public abstract boolean	Returns: true if the current page is the rightmost leaf of the tree, else return false. isRightmostLeaf() Is the current page the rightmost leaf of tree?
pack-priv void	linkRight(OpenBTree btree, ControlRow target) Link this page to the right of the target page.
public abstract void	printTree(OpenBTree btree) Recursively print the tree starting at current node in tree.
public void	release() Release this control row's resources.
public abstract ControlRow	search(SearchParameters search_params) Perform a recursive search, ultimately returning the latched leaf page and row slot after which the given key belongs.
protected void	searchForEntry(SearchParameters the parameters of the search params) Search this index page.
protected void	searchForEntryBackward(SearchParameters params)
protected abstract ControlRow	Returns: The leftmost leaf page. searchLeft(OpenBTree The open btree to associate latches/locks with. btree) Search and return the left most leaf page.
protected abstract ControlRow	Returns: The rightmost leaf page. searchRight(OpenBTree The open btree to associate latches/locks with. btree) Search and return the right most leaf page.
protected void	setIsRoot(boolean isRoot)
protected void	setLeftSibling(ControlRow leftsib)
protected void	setLevel(int newlevel)
pack-priv void	setParent(long parent)
protected void	setRightSibling(ControlRow rightsib)
protected void	setVersion(int version) Set version of the control row.
protected abstract boolean	shrinkFor(OpenBTree btree, DataValueDescriptor[] key) Perform a recursive shrink operation for the key.
protected abstract long	Returns: page number of the newly allocated leaf page created by split. splitFor(OpenBTree The open btree to associate latches with. open_btree, DataValueDescriptor[] A scratch area to use while searching for split pass. template, BranchControlRow The parent page of the current page in the split pass. starts at null for root. parentpage, DataValueDescriptor[] The key to make room for during the split pass. row, int A flag used to direct where point of split should be chosen. flag) Perform a top down split pass making room for the the key in "row".
public String	toString() Overrides java.lang.Object.toString. The standard toString().
pack-priv boolean	unlink(OpenBTree btree) Unlink this page from its siblings.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll wait wait wait

Field Detail

btree	back to summary
private BTree btree A copy of the Conglomerate that describes the owning conglom. This information is used during logical undo to get the type information so that rows can be compared and searched for. We may be able to get away with a subset of the information stored in the conglomerate. RESOLVE (mikem) - change this to only store the info on the root page.

btree

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private BTree btree

A copy of the Conglomerate that describes the owning conglom.

This information is used during logical undo to get the type information so that rows can be compared and searched for. We may be able to get away with a subset of the information stored in the conglomerate.

RESOLVE (mikem) - change this to only store the info on the root page.

CR_COLID_FIRST	back to summary
protected static final int CR_COLID_FIRST Column number assignments for columns of the control row. The control row is stored as the first row in a btree page. The row is an array of columns. The Control row columns are the columns numbered from ControlRow.CR_COLID_FIRST through ControlRow.CR_COLID_LAST. The classes which implement the concrete derived classes of ControlRow may add columns to the control row, but they must be added after the ControlRow columns.

CR_COLID_FIRST

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protected static final int CR_COLID_FIRST

Column number assignments for columns of the control row.

The control row is stored as the first row in a btree page. The row is an array of columns. The Control row columns are the columns numbered from ControlRow.CR_COLID_FIRST through ControlRow.CR_COLID_LAST. The classes which implement the concrete derived classes of ControlRow may add columns to the control row, but they must be added after the ControlRow columns.

CR_COLID_LAST	back to summary
protected static final int CR_COLID_LAST

CR_CONGLOM_BITSET	back to summary
protected static final FormatableBitSet CR_CONGLOM_BITSET

CR_CONGLOM_COLID	back to summary
protected static final int CR_CONGLOM_COLID

CR_ISROOT_BITSET	back to summary
protected static final FormatableBitSet CR_ISROOT_BITSET

CR_ISROOT_COLID	back to summary
protected static final int CR_ISROOT_COLID

CR_LEFTSIB_BITSET	back to summary
protected static final FormatableBitSet CR_LEFTSIB_BITSET

CR_LEFTSIB_COLID	back to summary
protected static final int CR_LEFTSIB_COLID

CR_LEVEL_BITSET	back to summary
protected static final FormatableBitSet CR_LEVEL_BITSET

CR_LEVEL_COLID	back to summary
protected static final int CR_LEVEL_COLID

CR_NCOLUMNS	back to summary
protected static final int CR_NCOLUMNS

CR_PARENT_BITSET	back to summary
protected static final FormatableBitSet CR_PARENT_BITSET

CR_PARENT_COLID	back to summary
protected static final int CR_PARENT_COLID

CR_RIGHTSIB_BITSET	back to summary
protected static final FormatableBitSet CR_RIGHTSIB_BITSET

CR_RIGHTSIB_COLID	back to summary
protected static final int CR_RIGHTSIB_COLID

CR_SLOT	back to summary
protected static final int CR_SLOT The slot at which all control rows reside.

CR_VERSION_BITSET	back to summary
protected static final FormatableBitSet CR_VERSION_BITSET bit sets used to fetch single columns at a time.

CR_VERSION_COLID	back to summary
protected static final int CR_VERSION_COLID

fetchDesc	back to summary
protected FetchDescriptor fetchDesc FetchDescriptor used to replace fetchFieldFromSlot() calls.

isRoot	back to summary
private SQLLongint isRoot Is this page the root of the btree? Currently "1" if the page is the root page, else "0". RESOLVE (mikem) When real datatype come about, this value should probably be just a bit in some status word.

isRoot

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private SQLLongint isRoot

Is this page the root of the btree?

Currently "1" if the page is the root page, else "0".

RESOLVE (mikem) When real datatype come about, this value should probably be just a bit in some status word.

last_search_result	back to summary
protected transient int last_search_result In memory hint about where to begin the binary search to find a key on the the current control page.

leftSiblingPageNumber	back to summary
private SQLLongint leftSiblingPageNumber Pointer to page which is "left" at the current level. Currently all pages at a level are doubly linked. The leftmost page in a level has a leftSiblingPageNumber == ContainerHandle.INVALID_PAGE_NUMBER. All key values on the page which is left must precede the first key value on the current page.

leftSiblingPageNumber

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private SQLLongint leftSiblingPageNumber

Pointer to page which is "left" at the current level.

Currently all pages at a level are doubly linked. The leftmost page in a level has a leftSiblingPageNumber == ContainerHandle.INVALID_PAGE_NUMBER. All key values on the page which is left must precede the first key value on the current page.

level	back to summary
private SQLLongint level The level of the btree. The leaf level of the btree is 0. The first branch level (parent level of the leaf), is level 1. The height of the btree is (level + 1). The smallest btree is a one page btree with only a leaf, and no branch pages.

level

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private SQLLongint level

The level of the btree.

The leaf level of the btree is 0. The first branch level (parent level of the leaf), is level 1. The height of the btree is (level + 1).

The smallest btree is a one page btree with only a leaf, and no branch pages.

page	back to summary
protected Page page The page that this control row describes.

parentPageNumber	back to summary
private SQLLongint parentPageNumber The parent page of the current page. For consistency checking it is useful to maintain the parentPageNumber field of the current page. The root page has a value of ContainerHandle.INVALID_PAGE_NUMBER in it's parentPageNumber field. RESOLVE (mikem) - we need to come up with some way to not maintain these, maybe by providing a property on secondary index or a different 2nd index.

parentPageNumber

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private SQLLongint parentPageNumber

The parent page of the current page.

For consistency checking it is useful to maintain the parentPageNumber field of the current page. The root page has a value of ContainerHandle.INVALID_PAGE_NUMBER in it's parentPageNumber field.

RESOLVE (mikem) - we need to come up with some way to not maintain these, maybe by providing a property on secondary index or a different 2nd index.

rightSiblingPageNumber	back to summary
private SQLLongint rightSiblingPageNumber Pointer to page which is "right" at the current level. Currently all pages at a level are doubly linked. The rightmost page in a level has a rightSiblingPageNumber == ContainerHandle.INVALID_PAGE_NUMBER. All key values on the page which is right of the current page must follow the last key value on the current page.

rightSiblingPageNumber

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private SQLLongint rightSiblingPageNumber

Pointer to page which is "right" at the current level.

Currently all pages at a level are doubly linked. The rightmost page in a level has a rightSiblingPageNumber == ContainerHandle.INVALID_PAGE_NUMBER. All key values on the page which is right of the current page must follow the last key value on the current page.

row	back to summary
protected DataValueDescriptor[] row The page that this control row describes.

scratch_row	back to summary
protected DataValueDescriptor[] scratch_row row used to replace fetchFieldFromSlot() calls.

SPLIT_FLAG_FIRST_IN_TABLE	back to summary
public static final int SPLIT_FLAG_FIRST_IN_TABLE

SPLIT_FLAG_FIRST_ON_PAGE	back to summary
public static final int SPLIT_FLAG_FIRST_ON_PAGE

SPLIT_FLAG_LAST_IN_TABLE	back to summary
public static final int SPLIT_FLAG_LAST_IN_TABLE

SPLIT_FLAG_LAST_ON_PAGE	back to summary
public static final int SPLIT_FLAG_LAST_ON_PAGE Values passed in the flag argument to splitFor.

use_last_search_result_hint	back to summary
protected transient boolean use_last_search_result_hint In memory hint about whether to use the last_search_result hint during search.

version	back to summary
private StorableFormatId version Version indentifier of the control row within the page. This is the format id of the control row. The format id is currently one of either StoredFormatIds.ACCESS_BTREE_LEAFCONTROLROW_ID or StoredFormatIds.ACCESS_BTREE_BRANCHCONTROLROW_ID.

version

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private StorableFormatId version

Version indentifier of the control row within the page.

This is the format id of the control row. The format id is currently one of either StoredFormatIds.ACCESS_BTREE_LEAFCONTROLROW_ID or StoredFormatIds.ACCESS_BTREE_BRANCHCONTROLROW_ID.

Constructor Detail

ControlRow	back to summary
protected ControlRow() No arg constructor. GetControlRowForPage() will call this constructor when it uses the monitor to create a control row dynamically given a given format id.

ControlRow

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protected ControlRow()

No arg constructor.

GetControlRowForPage() will call this constructor when it uses the monitor to create a control row dynamically given a given format id.

ControlRow	back to summary
protected ControlRow(OpenBTree btree, Page page, int level, ControlRow parent, boolean isRoot) throws StandardException Constructor for making a new control row as part of allocating a new page. Fills in all the fields but does not write them anywhere. Changes to this constructor will probably require changes to the corresponding accessor(s). Parameters btree:OpenBTree Static information about the btree. page:Page The page described by this control row. parent:ControlRow The parent page of this page, "null" if this page is root or if not maintaining parent links. isRoot:boolean Is this page the root of the tree? Exceptions StandardException: Standard exception policy.

ControlRow

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protected ControlRow(OpenBTree btree, Page page, int level, ControlRow parent, boolean isRoot) throws StandardException

Constructor for making a new control row as part of allocating a new page. Fills in all the fields but does not write them anywhere.

Changes to this constructor will probably require changes to the corresponding accessor(s).

Parameters

btree:OpenBTree: Static information about the btree.
page:Page: The page described by this control row.
parent:ControlRow: The parent page of this page, "null" if this page is root or if not maintaining parent links.
isRoot:boolean: Is this page the root of the tree?

Exceptions

StandardException:: Standard exception policy.

ControlRow	back to summary
protected ControlRow(ContainerHandle container, Page page) throws StandardException Constructor for making a control row for an existing page. Not all the fields are filled in; their values will get faulted in from the page as necessary. Classes which extend ControlRow must delegate to this constructor and may want to override it as well. Changes to this constructor will probably require changes to the corresponding accessor(s). Parameters container:ContainerHandle Open container page:Page The page described by this control row. Exceptions StandardException: Standard exception policy.

ControlRow

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protected ControlRow(ContainerHandle container, Page page) throws StandardException

Constructor for making a control row for an existing page.

Not all the fields are filled in; their values will get faulted in from the page as necessary.

Classes which extend ControlRow must delegate to this constructor and may want to override it as well. Changes to this constructor will probably require changes to the corresponding accessor(s).

Parameters

container:ContainerHandle: Open container
page:Page: The page described by this control row.

Exceptions

StandardException:: Standard exception policy.

Method Detail

auxObjectInvalidated back to summary

auxObjectInvalidated	back to summary
public void auxObjectInvalidated() Implements org.apache.derby.iapi.store.raw.AuxObject.auxObjectInvalidated. Called when the page is being evicted from cache or when a rollback happened on the page and may possibly have changed the control row's value See Also `AuxObject#auxObjectInvalidated`

public void auxObjectInvalidated()

Implements org.apache.derby.iapi.store.raw.AuxObject.auxObjectInvalidated.

Called when the page is being evicted from cache or when a rollback happened on the page and may possibly have changed the control row's value

See Also: AuxObject#auxObjectInvalidated

checkConsistency	back to summary
protected abstract int checkConsistency(OpenBTree btree, ControlRow parent, boolean check_other_pages) throws StandardException Check consistency of the page and its children, returning the number of pages seen, and throwing errors if inconsistencies are found. Parameters btree:OpenBTree The open btree to associate latches/locks with. parent:ControlRow The parent page of this page, "null" if this page is root or if not maintaining parent links. check_other_pages:boolean Should the consistency check go to other pages (this option breaks the latch protocol). Returns:int The identifier to be used to open the conglomerate later. Exceptions StandardException: Standard exception policy.

checkConsistency

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protected abstract int checkConsistency(OpenBTree btree, ControlRow parent, boolean check_other_pages) throws StandardException

Check consistency of the page and its children, returning the number of pages seen, and throwing errors if inconsistencies are found.

Parameters

btree:OpenBTree: The open btree to associate latches/locks with.
parent:ControlRow: The parent page of this page, "null" if this page is root or if not maintaining parent links.
check_other_pages:boolean: Should the consistency check go to other pages (this option breaks the latch protocol).

Returns:int

The identifier to be used to open the conglomerate later.

Exceptions

StandardException:: Standard exception policy.

checkGeneric	back to summary
protected void checkGeneric(OpenBTree btree, ControlRow parent, boolean check_other_pages) throws StandardException Perform consistency checks which are common to all pages that derive from ControlRow (both leaf and branch pages). The checks are: This page thinks the parent argument is actually its parent. The level of this page is 1 less than the level of the parent. All the rows on the page are in order. Both left and right siblings, if they exist, are at the same level of this page. This page is the left sibling of its right sibling, and it's the right sibling of its left sibling. The last row on the left sibling is < the first row on this page. The first row on the right sibling is > than the the last row on this page. Note that these last two are really only true if there are never duplicate keys. Exceptions StandardException: Standard exception policy.

checkGeneric

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protected void checkGeneric(OpenBTree btree, ControlRow parent, boolean check_other_pages) throws StandardException

Perform consistency checks which are common to all pages that derive from ControlRow (both leaf and branch pages). The checks are:

This page thinks the parent argument is actually its parent.

The level of this page is 1 less than the level of the parent.

All the rows on the page are in order.

Both left and right siblings, if they exist, are at the same level of this page.

This page is the left sibling of its right sibling, and it's the right sibling of its left sibling.

The last row on the left sibling is < the first row on this page.

The first row on the right sibling is > than the the last row on this page.

Note that these last two are really only true if there are never duplicate keys.

Exceptions

StandardException:: Standard exception policy.

checkRowOrder	back to summary
protected boolean checkRowOrder(OpenBTree btree, ControlRow parent) throws StandardException Check that all rows on the page are in order. This means that each key is > than the previous key. Exceptions StandardException: Standard exception policy.

checkRowOrder

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protected boolean checkRowOrder(OpenBTree btree, ControlRow parent) throws StandardException

Check that all rows on the page are in order. This means that each key is > than the previous key.

Exceptions

StandardException:: Standard exception policy.

checkSiblings	back to summary
protected void checkSiblings(OpenBTree btree) throws StandardException Perform checks on the siblings of this page: make sure that they're at the same level as this page, that they're mutually linked together, and that the first/last keys on sibling pages are in order. Exceptions StandardException: Standard exception policy.

checkSiblings

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protected void checkSiblings(OpenBTree btree) throws StandardException

Perform checks on the siblings of this page: make sure that they're at the same level as this page, that they're mutually linked together, and that the first/last keys on sibling pages are in order.

Exceptions

StandardException:: Standard exception policy.

compareIndexRowFromPageToKey	back to summary
public static int compareIndexRowFromPageToKey(ControlRow indexpage, int slot, DataValueDescriptor[] indexrow, DataValueDescriptor[] key, int nCompareCols, int partialKeyOrder, boolean[] ascOrDesc) throws StandardException Compare two orderable rows, considering nCompareCols, and return -1, 0, or 1 depending on whether the first row (indexrow) is less than, equal to, or greater than the second (key). The key may have fewer columns present than nCompareCols. In such a case, if all the columns of the partial key match all of the corresponding columns in the index row, then the value passed in in partialKeyOrder is returned. The caller should pass in partialKeyOrder=1 if the index rows which match a partial key should be considered to be greater than the partial key, and -1 if they should be considered to be less. This routine only reads objects off the page if it needs them, so if a multi-part key differs in the first column the subsequent columns are not read. Parameters indexpage:ControlRow Controlrow of page to get target row from. slot:int Slot to get control row from. indexrow:DataValueDescriptor[] template of the target row (the row in the index). key:DataValueDescriptor[] the (possibly partial) search key. nCompareCols:int the number of columns to compare. partialKeyOrder:int what to return on a partial key match. ascOrDesc:boolean[] column sort order information Exceptions StandardException: if lower levels have a problem.

compareIndexRowFromPageToKey

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public static int compareIndexRowFromPageToKey(ControlRow indexpage, int slot, DataValueDescriptor[] indexrow, DataValueDescriptor[] key, int nCompareCols, int partialKeyOrder, boolean[] ascOrDesc) throws StandardException

Compare two orderable rows, considering nCompareCols, and return -1, 0, or 1 depending on whether the first row (indexrow) is less than, equal to, or greater than the second (key). The key may have fewer columns present than nCompareCols. In such a case, if all the columns of the partial key match all of the corresponding columns in the index row, then the value passed in in partialKeyOrder is returned. The caller should pass in partialKeyOrder=1 if the index rows which match a partial key should be considered to be greater than the partial key, and -1 if they should be considered to be less. This routine only reads objects off the page if it needs them, so if a multi-part key differs in the first column the subsequent columns are not read.

Parameters

indexpage:ControlRow: Controlrow of page to get target row from.
slot:int: Slot to get control row from.
indexrow:DataValueDescriptor[]: template of the target row (the row in the index).
key:DataValueDescriptor[]: the (possibly partial) search key.
nCompareCols:int: the number of columns to compare.
partialKeyOrder:int: what to return on a partial key match.
ascOrDesc:boolean[]: column sort order information

Exceptions

StandardException:: if lower levels have a problem.

compareIndexRowToKey	back to summary
public static int compareIndexRowToKey(DataValueDescriptor[] indexrow, DataValueDescriptor[] key, int nCompareCols, int partialKeyOrder, boolean[] ascOrDesc) throws StandardException

compareRowsOnSiblings	back to summary
protected boolean compareRowsOnSiblings(OpenBTree btree, ControlRow left_sib, ControlRow right_sib) throws StandardException

controlRowInit	back to summary
protected abstract void controlRowInit() Perform page specific initialization.

controlRowInit

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protected abstract void controlRowInit()

Perform page specific initialization.

debugPage

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public String debugPage(OpenBTree open_btree) throws StandardException

Dump complete information about control row and rows on the page.

Returns:String

string with all info.

Exceptions

StandardException:: Standard exception policy.

get

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public static ControlRow get(OpenBTree open_btree, long pageNumber) throws StandardException

Get the control row from the given page in the b-tree. The returned control row will be of the correct type for the page (i.e., either a LeafControlRow or a BranchControlRow).

Exceptions

StandardException:: Standard exception policy.

get	back to summary
public static ControlRow get(ContainerHandle container, long pageNumber) throws StandardException

getConglom

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public BTree getConglom(int format_id) throws StandardException

Get format id information for row on page.

Returns the format id information for a row on the page. faulting it in from the page if necessary.

Returns:BTree

format id of a row on the page.

Exceptions

StandardException:: Standard exception policy.

getControlRowForPage	back to summary
protected static ControlRow getControlRowForPage(ContainerHandle container, Page page) throws StandardException

getIsRoot	back to summary
protected boolean getIsRoot() throws StandardException

getLeftChild

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protected abstract ControlRow getLeftChild(OpenBTree btree) throws StandardException

Return the left child pointer for the page.

Leaf pages don't have children, so they override this and return null.

Parameters

btree:OpenBTree: The open btree to associate latches/locks with.

Returns:ControlRow

The page which is the leftmost child of this page.

Exceptions

StandardException:: Standard exception policy.

getLeftSibling

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public ControlRow getLeftSibling(OpenBTree btree) throws StandardException, WaitError

Get the control row for this page's left sibling, or null if there is no left sibling (which probably means it's the leftmost page at its level). Since right-to-left traversal of an index level is deadlock-prone, this method will only get get the left sibling if it can latch it without waiting.

Exceptions

StandardException:: Standard exception policy.
WaitError:: if the latch request would have had to wait.

getleftSiblingPageNumber

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public long getleftSiblingPageNumber() throws StandardException

Get the page number of the left sibling. Fault it's value in if it hasn't been yet.

Exceptions

StandardException:: Standard exception policy.

getLevel	back to summary
protected int getLevel() throws StandardException

getNoWait

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public static ControlRow getNoWait(OpenBTree open_btree, long pageNumber) throws StandardException

Get the control row for the given page if the latch on the page can be obtained without waiting, else return null.

Exceptions

StandardException:: Standard exception policy.

getNumberOfControlRowColumns

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protected abstract int getNumberOfControlRowColumns()

Get the number of columns in the control row.

Control rows all share the first columns as defined by this class and then add columns to the end of the control row. For instance a branch control row add a child page pointer field.

Returns:int: The total number of columns in the control row.

getPage	back to summary
public Page getPage()

getParentPageNumber

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protected long getParentPageNumber() throws StandardException

Get the page number of the parent, if it's being maintained. Note that there is intentionally no way to get the control row for the parent page - the b-tree code NEVER traverses up the tree, even in consistency checks.

Exceptions

StandardException:: Standard exception policy.

getRightChild

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protected abstract ControlRow getRightChild(OpenBTree btree) throws StandardException

Return the right child pointer for the page.

Leaf pages don't have children, so they override this and return null.

Parameters

btree:OpenBTree: The open btree to associate latches/locks with.

Returns:ControlRow

The page which is the rightmost child of this page.

Exceptions

StandardException:: Standard exception policy.

getRightSibling

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protected ControlRow getRightSibling(OpenBTree open_btree) throws StandardException

Return the control row for this page's right sibling. Unlike getting the left sibling, it's ok to wait for the right sibling latch since left-to-right is the deadlock-free ordering.

Exceptions

StandardException:: Standard exception policy.

getrightSiblingPageNumber

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protected long getrightSiblingPageNumber() throws StandardException

Get the page number of the right sibling. Fault it's value in if it hasn't been yet.

Exceptions

StandardException:: Standard exception policy.

getRow

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protected final DataValueDescriptor[] getRow()

Get the row.

Return the object array that represents the control row for use in raw store fetch, insert, and/or update.

Returns:DataValueDescriptor[]: The row.

getRowTemplate

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public DataValueDescriptor[] getRowTemplate(OpenBTree open_btree) throws StandardException

Return a new template for reading a data row from the current page.

Default implementation for rows which are the same as the conglomerates template, sub-classes can alter if underlying template is different (for instance branch rows add an extra field at the end).

Returns:DataValueDescriptor[]

Newly allocated template.

Exceptions

StandardException:: Standard exception policy.

getVersion

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protected int getVersion() throws StandardException

Get version of the control row.

Returns the version of the control row, faulting it in from the page if necessary.

Returns:int

version of the control row.

Exceptions

StandardException:: Standard exception policy.

isLeftmostLeaf

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public abstract boolean isLeftmostLeaf() throws StandardException

Is the current page the leftmost leaf of tree?

Returns:boolean

true if the current page is the leftmost leaf of the tree, else return false.

Exceptions

StandardException:: Standard exception policy.

isRightmostLeaf

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public abstract boolean isRightmostLeaf() throws StandardException

Is the current page the rightmost leaf of tree?

Returns:boolean

true if the current page is the rightmost leaf of the tree, else return false.

Exceptions

StandardException:: Standard exception policy.

linkRight

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pack-priv void linkRight(OpenBTree btree, ControlRow target) throws StandardException

Link this page to the right of the target page.

Upon entry, this page and the target must be latched. Upon exit, this page and the target remain latched.

This method carefully acquires pages from left to right in order to avoid deadlocks.

Exceptions

StandardException:: Standard exception policy.

printTree

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public abstract void printTree(OpenBTree btree) throws StandardException

Recursively print the tree starting at current node in tree.

Exceptions

StandardException:: Standard exception policy.

release	back to summary
public void release() Release this control row's resources.

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public abstract ControlRow search(SearchParameters search_params) throws StandardException

Perform a recursive search, ultimately returning the latched leaf page and row slot after which the given key belongs. The slot is returned in the result structure. If the key exists on the page, the resultExact field will be true. Otherwise, resultExact field will be false, and the row slot returned will be the one immediately preceding the position at which the key belongs.

Exceptions

StandardException:: Standard exception policy.

searchForEntry back to summary

protected void searchForEntry(SearchParameters params) throws StandardException

Search this index page.

This method is very performance sensitive. It is the intention that no object allocations occur during the execution of this method.

This method performs a binary search on the page and finds the entry i on the page such that entry[i] <= key < entry[i+1]. The result of the search is filled into the passed in params structure.

Parameters

params:SearchParameters: the parameters of the search

Exceptions

StandardException:: could be thrown by underlying raw store operations.

See Also

SearchParameters

searchForEntryBackward	back to summary
protected void searchForEntryBackward(SearchParameters params) throws StandardException

searchLeft

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protected abstract ControlRow searchLeft(OpenBTree btree) throws StandardException

Search and return the left most leaf page.

Perform a recursive search, ultimately returning the leftmost leaf page which is the first leaf page in the leaf sibling chain. (This method might better be called getFirstLeafPage()).

Parameters

btree:OpenBTree: The open btree to associate latches/locks with.

Returns:ControlRow

The leftmost leaf page.

Exceptions

StandardException:: Standard exception policy.

searchRight

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protected abstract ControlRow searchRight(OpenBTree btree) throws StandardException

Search and return the right most leaf page.

Perform a recursive search, ultimately returning the rightmost leaf page which is the last leaf page in the leaf sibling chain. (This method might better be called getLastLeafPage()).

Parameters

btree:OpenBTree: The open btree to associate latches/locks with.

Returns:ControlRow

The rightmost leaf page.

Exceptions

StandardException:: Standard exception policy.

setIsRoot	back to summary
protected void setIsRoot(boolean isRoot) throws StandardException

setLeftSibling	back to summary
protected void setLeftSibling(ControlRow leftsib) throws StandardException

setLevel	back to summary
protected void setLevel(int newlevel) throws StandardException

setParent	back to summary
pack-priv void setParent(long parent) throws StandardException

setRightSibling	back to summary
protected void setRightSibling(ControlRow rightsib) throws StandardException

setVersion

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protected void setVersion(int version) throws StandardException

Set version of the control row.

Sets the version of the control row. Updates both the in-memory control row and the disk copy.

Exceptions

StandardException:: Standard exception policy.

shrinkFor

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protected abstract boolean shrinkFor(OpenBTree btree, DataValueDescriptor[] key) throws StandardException

Perform a recursive shrink operation for the key. If this method returns true, the caller should remove the corresponding entry for the page. This routine is not guaranteed to successfully shrink anything. The page lead to by the key might turn out not to be empty by the time shrink gets there, and shrinks will give up if there is a deadlock.

As currently implemented shrinkFor must be executed while holding an exclusive container lock on the entire table. It is expected that this call is made within an internal transaction which has been called by a post commit thread. Latches are released by the code. The raw store guarantees that deallocated pages are not seen by other xacts until the transaction has been committed.

Note that a non-table level lock implementation must hold latches on pages affected until end transaction.

On entry, the current page is latched. On exit, all pages will have been unlatched.

Exceptions

StandardException:: Standard exception policy.

splitFor

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protected abstract long splitFor(OpenBTree open_btree, DataValueDescriptor[] template, BranchControlRow parentpage, DataValueDescriptor[] row, int flag) throws StandardException

Perform a top down split pass making room for the the key in "row".

Perform a split such that a subsequent call to insert given the argument index row will likely find room for it. Since latches are released the client must code for the case where another user has grabbed the space made available by the split pass and be ready to do another split.

Parameters

open_btree:OpenBTree: The open btree to associate latches with.
template:DataValueDescriptor[]: A scratch area to use while searching for split pass.
parentpage:BranchControlRow: The parent page of the current page in the split pass. starts at null for root.
row:DataValueDescriptor[]: The key to make room for during the split pass.
flag:int: A flag used to direct where point of split should be chosen.

Returns:long

page number of the newly allocated leaf page created by split.

Exceptions

StandardException:: Standard exception policy.

toString

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public String toString()

Overrides java.lang.Object.toString.

The standard toString().

This is a concise print out of the info in the control row, does not include anything the page.

Returns:String

Doc from java.lang.Object.toString.

a string representation of the object

unlink

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pack-priv boolean unlink(OpenBTree btree) throws StandardException

Unlink this page from its siblings. This method will give up and return false rather than run the risk of a deadlock.

On entry this page must be latched. The siblings are latched and unlatched during the operation. Upon exit, this page will remain latched, but unlinked from its siblings and deallocated from the container.

The seemingly odd situation that this page will be returned latched but deallocated is intentional. The container will not be able to reuse this page until the latch is released, and the caller may still need to read information out of it.

Exceptions

StandardException:: Standard exception policy.

public abstract Class ControlRow

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail