Java Doc for BranchControlRow.java in  » Database-DBMS » db-derby-10.2 » org » apache » derby » impl » store » access » btree » Java Source Code / Java DocumentationJava Source Code and Java Documentation

Perform a recursive search, ultimately returning the leftmost leaf page which is the first leaf page in the leaf sibling chain.

Perform a recursive search, ultimately returning the rightmost leaf page which is the last leaf page in the leaf sibling chain.

Perform a split such that a subsequent call to insert given the argument index row will likely find room for it.

Public no arg constructor is for the monitor to call for format id implementation, it should not be called for any other reason.

Leaf pages don't have children, so they override this and return null. The page which is the leftmost child of this page.
Parameters:
  open_btree - The open btree to associate latches/locks with.
exception:
  StandardException - Standard exception policy.

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.

The total number of columns in the control row.

Leaf pages don't have children, so they override this and return null. The page which is the rightmost child of this page.
Parameters:
  open_btree - The open btree to associate latches/locks with.
exception:
  StandardException - Standard exception policy.

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). Newly allocated template.
exception:
  StandardException - Standard exception policy.

true if the current page is the leftmost leaf of the tree,else return false.
exception:
  StandardException - Standard exception policy.

true if the current page is the rightmost leaf of the tree,else return false.
exception:
  StandardException - Standard exception policy.

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()). The leftmost leaf page.
Parameters:
  btree - The open btree to associate latches/locks with.
exception:
  StandardException - Standard exception policy.

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()). The rightmost leaf page.
Parameters:
  btree - The open btree to associate latches/locks with.
exception:
  StandardException - Standard exception policy.

The receiver page must be latched on entry and is returned latched.
exception:
  StandardException - Standard exception policy.

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.

Latches: o PARENT : is latched on entry (unless the split is the root then there is no parent. o THISBRANCH: the current page is latched on entry. o CHILD : latch the child page which will be pointed at by the left child pointer of the new page. RESOLVE (mikem) -see comments below o NEWPAGE : Allocate and latch new page. o CHILD : release. (RESOLVE) o fixparents: latch pages and reset their parent pointers. Conditionally fix up the parent links on the pages pointed at by the newly allocated page. First get latch and release on the left child page and then loop through slots on NEWPAGE, from left to right getting and releasing latches. page number of the newly allocated leaf page created by split.
Parameters:
  open_btree - The open btree to associate latches with.
Parameters:
  template - A scratch area to use while searching for split pass.
Parameters:
  parent - The parent page of the current page in the split pass.starts at null for root.
Parameters:
  splitrow - The key to make room for during the split pass.
Parameters:
  flag - A flag used to direct where point of split should bechosen.
exception:
  StandardException - Standard exception policy.